Lung Cancer

People with cancer are often desperate to know what caused their disease. Was it something they did? Something they could have prevented?

vitanovski/Thinkstock.com

In a recent analysis, experts estimated that about 40% of cancers can be explained by known, often modifiable risk factors. Smoking and obesity represent the primary drivers, though a host of other factors – germline mutations, alcohol, infections, or environmental pollutants like asbestos – contribute to cancer risk as well.

But what about the remaining 60% of cancers?

The study suggests that, although many of these cases likely have an underlying lifestyle or environmental component, experts still do not fully understand their origin story. And a small but significant number may simply be caused by chance.

Here’s what experts suspect those missing causes might be, and why they can be so difficult to confirm.
 

Possibility 1: Known risk factors contribute more than we realize

For certain factors, a straight line can be drawn to cancer.

Take smoking, for instance. Decades of research have helped scientists clearly delineate tobacco’s carcinogenic effects. Researchers have pinpointed a unique set of mutations in the tumors of smokers that can be seen when cells grown in a dish are exposed to the carcinogens present in tobacco.

In addition, experts have been able to collect robust data from epidemiologic studies on smoking prevalence as well as associated cancer risks and deaths, in large part because an individual’s lifetime tobacco exposure is fairly easy to measure.

“The evidence for smoking is incredibly consistent,” Paul Brennan, PhD, a cancer epidemiologist at the World Health Organization’s International Agency for Research on Cancer, said in an interview.

For other known risk factors, such as obesity and air pollution, many more questions than answers remain.

Because of the limitations in how such factors are measured, we are likely downplaying their effects, said Richard Martin, PhD, a professor of clinical epidemiology at the University of Bristol (England).

Take obesity. Excess body weight is associated with an increased risk of at least 13 cancers. Although risk estimates vary by study and cancer type, according to a global snapshot from 2012, being overweight or obese accounted for about 4% of all cancers worldwide – 1% in low-income countries and as high as 8% in high-income countries.

However, Dr. Brennan believes “we have underestimated the effect of obesity [on cancer].”

A key reason, he said, is most studies use body mass index to determine whether someone is overweight or obese, but BMI is a poor measure of body fat. BMI does not differentiate between fat and muscle, which means two people with the same height and weight can have the same BMI, even if one is an athlete who eats lean meats and vegetables while the other lives a sedentary life and consumes large quantities of processed foods and alcohol.

On top of that, studies often only calculate a person’s BMI once, and a single measurement can’t tell you how a person’s weight has fluctuated in recent years or across different stages of their life. However, recent analyses suggest that obesity status over time may be more relevant to cancer risk than one-off measures.

In addition, many studies now suggest that alterations to our gut microbes and high blood insulin level – often seen in people who are overweight or obese – may increase the risk of cancer and speed the growth of tumors.

When these additional factors are considered, the impact of excess body fat may ultimately play a much more significant role in cancer risk. In fact, according to Dr. Brennan, “if we estimate [the effects of obesity] properly, it might at some point become the main cause of cancer.”
 

Possibility 2: Environmental or lifestyle factors remain under the radar

Researchers have linked many substances we consume or are exposed to in our daily lives – air pollution, toxins from industrial waste, and highly processed foods – to cancer. But the extent or contribution of potential carcinogens in our surroundings, particularly those found almost everywhere at low levels, is still largely unknown.

One simple reason is the effects of many of these substances remain difficult to assess. For instance, it is much harder to study the impact of pollutants found in food or water, in which a given population will share similar exposure levels versus tobacco, where it is possible to compare a person who smokes a pack of cigarettes a day with a person who does not smoke.

“If you’ve got exposures that are ubiquitous, it can be difficult to discern their [individual] roles,” Dr. Martin said. “There are many causes that we [likely] don’t really know because everyone has been exposed.”

On the flip side, some carcinogenic substances that people encounter for limited periods might be missed if studies are not performed at the time of exposure.

“What’s in the body at age 40 may not reflect what you were exposed at age 5-10 on the playground or soccer field,” said Graham Colditz, MD, PhD, an epidemiologist and public health expert at Washington University, St. Louis. “The technology keeps changing so we can get better measures of what you’ve got exposure to today, but how that relates to 5, 10, 15 years ago is probably very variable.”

In addition, researchers have found that many carcinogens do not cause specific mutations in a cell’s DNA; rather, studies suggest that most carcinogens lead to cancer-promoting changes in cells, such as inflammation.

“We need to think of how potential carcinogens are causing cancer,” Dr. Brennan said. Instead of provoking mutations, potential carcinogens may use a “whole other kind of pathway.” When, for instance, inflammation becomes chronic, it may spur a cascade of events that ultimately leads to cancer.

Finally, not much is known about what causes cancers in low- and middle-income countries. Most of the research to date has been in high-income countries, such the United States, Australia, and parts of Europe.

“There’s a real lack of robust epidemiological studies in other parts of the world, Latin America, Africa, parts of Asia,” Marc Gunter, PhD, a molecular epidemiologist at the IARC, told this news organization.
 

Possibility 3: Some cancers occur by chance

When it comes to cancer risk, an element of chance may be at play. Cancer can occur in individuals who have very little exposure to known carcinogens or have no family history of cancer.

“We all know there are people who get cancer who eat very healthy diets, are never overweight, and never smoke,” Dr. Gunter said. “Then there are people on the other end of the extreme who don’t get cancer.”

But what fraction of cancers are attributable to chance?

A controversial 2017 study published in Science suggested that, based on the rate of cell turnover in healthy tissues in the lung, pancreas, and other parts of the body, only about one-third of cancers could be linked to environmental or genetic factors. The rest, the authors claimed, occurred because of random mutations that accumulated in a person’s DNA – in other words, bad luck.

That study brought on a flood of criticism from scientists who pointed to serious flaws in the work that led the researchers to significantly overestimate the share of chance-related cancers.

The actual proportion of cancers that occur by chance is much lower, according to Dr. Brennan. “If you look at international comparisons [of cancer rates] and take a conservative estimate, you see that maybe 10% or 15% of cancers are really chance.”

Whether some cancers are caused by bad luck or undiscovered risk factors remains an open question.

But the bottom line is many unknown causes of cancer are likely environmental or lifestyle related, which means that, in theory, they can be altered, even prevented.

“There is always going to be some element of chance, but you can modify your chance, depending on your lifestyle and maybe other factors, which we don’t fully understand yet,” Dr. Gunter said.

The good news is that, when it comes to prevention, there are many ways to modify our behaviors – such as consuming fewer processed meats, going for a daily walk, or getting vaccinated against cancer-causing viruses – to improve our chances of living cancer free. And as scientists better understand more about what causes cancer, possibilities for prevention will only grow.

“There is a constant, slow growth [in knowledge] that is lowering the overall risk of cancer,” Dr. Brennan said. “We’re never going to eliminate cancer, but we will be able to control it as a disease.”

A version of this article first appeared on Medscape.com.

People with cancer are often desperate to know what caused their disease. Was it something they did? Something they could have prevented?

vitanovski/Thinkstock.com

In a recent analysis, experts estimated that about 40% of cancers can be explained by known, often modifiable risk factors. Smoking and obesity represent the primary drivers, though a host of other factors – germline mutations, alcohol, infections, or environmental pollutants like asbestos – contribute to cancer risk as well.

But what about the remaining 60% of cancers?

The study suggests that, although many of these cases likely have an underlying lifestyle or environmental component, experts still do not fully understand their origin story. And a small but significant number may simply be caused by chance.

Here’s what experts suspect those missing causes might be, and why they can be so difficult to confirm.
 

Possibility 1: Known risk factors contribute more than we realize

For certain factors, a straight line can be drawn to cancer.

Take smoking, for instance. Decades of research have helped scientists clearly delineate tobacco’s carcinogenic effects. Researchers have pinpointed a unique set of mutations in the tumors of smokers that can be seen when cells grown in a dish are exposed to the carcinogens present in tobacco.

In addition, experts have been able to collect robust data from epidemiologic studies on smoking prevalence as well as associated cancer risks and deaths, in large part because an individual’s lifetime tobacco exposure is fairly easy to measure.

“The evidence for smoking is incredibly consistent,” Paul Brennan, PhD, a cancer epidemiologist at the World Health Organization’s International Agency for Research on Cancer, said in an interview.

For other known risk factors, such as obesity and air pollution, many more questions than answers remain.

Because of the limitations in how such factors are measured, we are likely downplaying their effects, said Richard Martin, PhD, a professor of clinical epidemiology at the University of Bristol (England).

Take obesity. Excess body weight is associated with an increased risk of at least 13 cancers. Although risk estimates vary by study and cancer type, according to a global snapshot from 2012, being overweight or obese accounted for about 4% of all cancers worldwide – 1% in low-income countries and as high as 8% in high-income countries.

However, Dr. Brennan believes “we have underestimated the effect of obesity [on cancer].”

A key reason, he said, is most studies use body mass index to determine whether someone is overweight or obese, but BMI is a poor measure of body fat. BMI does not differentiate between fat and muscle, which means two people with the same height and weight can have the same BMI, even if one is an athlete who eats lean meats and vegetables while the other lives a sedentary life and consumes large quantities of processed foods and alcohol.

On top of that, studies often only calculate a person’s BMI once, and a single measurement can’t tell you how a person’s weight has fluctuated in recent years or across different stages of their life. However, recent analyses suggest that obesity status over time may be more relevant to cancer risk than one-off measures.

In addition, many studies now suggest that alterations to our gut microbes and high blood insulin level – often seen in people who are overweight or obese – may increase the risk of cancer and speed the growth of tumors.

When these additional factors are considered, the impact of excess body fat may ultimately play a much more significant role in cancer risk. In fact, according to Dr. Brennan, “if we estimate [the effects of obesity] properly, it might at some point become the main cause of cancer.”
 

Possibility 2: Environmental or lifestyle factors remain under the radar

Researchers have linked many substances we consume or are exposed to in our daily lives – air pollution, toxins from industrial waste, and highly processed foods – to cancer. But the extent or contribution of potential carcinogens in our surroundings, particularly those found almost everywhere at low levels, is still largely unknown.

One simple reason is the effects of many of these substances remain difficult to assess. For instance, it is much harder to study the impact of pollutants found in food or water, in which a given population will share similar exposure levels versus tobacco, where it is possible to compare a person who smokes a pack of cigarettes a day with a person who does not smoke.

“If you’ve got exposures that are ubiquitous, it can be difficult to discern their [individual] roles,” Dr. Martin said. “There are many causes that we [likely] don’t really know because everyone has been exposed.”

On the flip side, some carcinogenic substances that people encounter for limited periods might be missed if studies are not performed at the time of exposure.

“What’s in the body at age 40 may not reflect what you were exposed at age 5-10 on the playground or soccer field,” said Graham Colditz, MD, PhD, an epidemiologist and public health expert at Washington University, St. Louis. “The technology keeps changing so we can get better measures of what you’ve got exposure to today, but how that relates to 5, 10, 15 years ago is probably very variable.”

In addition, researchers have found that many carcinogens do not cause specific mutations in a cell’s DNA; rather, studies suggest that most carcinogens lead to cancer-promoting changes in cells, such as inflammation.

“We need to think of how potential carcinogens are causing cancer,” Dr. Brennan said. Instead of provoking mutations, potential carcinogens may use a “whole other kind of pathway.” When, for instance, inflammation becomes chronic, it may spur a cascade of events that ultimately leads to cancer.

Finally, not much is known about what causes cancers in low- and middle-income countries. Most of the research to date has been in high-income countries, such the United States, Australia, and parts of Europe.

“There’s a real lack of robust epidemiological studies in other parts of the world, Latin America, Africa, parts of Asia,” Marc Gunter, PhD, a molecular epidemiologist at the IARC, told this news organization.
 

Possibility 3: Some cancers occur by chance

When it comes to cancer risk, an element of chance may be at play. Cancer can occur in individuals who have very little exposure to known carcinogens or have no family history of cancer.

“We all know there are people who get cancer who eat very healthy diets, are never overweight, and never smoke,” Dr. Gunter said. “Then there are people on the other end of the extreme who don’t get cancer.”

But what fraction of cancers are attributable to chance?

A controversial 2017 study published in Science suggested that, based on the rate of cell turnover in healthy tissues in the lung, pancreas, and other parts of the body, only about one-third of cancers could be linked to environmental or genetic factors. The rest, the authors claimed, occurred because of random mutations that accumulated in a person’s DNA – in other words, bad luck.

That study brought on a flood of criticism from scientists who pointed to serious flaws in the work that led the researchers to significantly overestimate the share of chance-related cancers.

The actual proportion of cancers that occur by chance is much lower, according to Dr. Brennan. “If you look at international comparisons [of cancer rates] and take a conservative estimate, you see that maybe 10% or 15% of cancers are really chance.”

Whether some cancers are caused by bad luck or undiscovered risk factors remains an open question.

But the bottom line is many unknown causes of cancer are likely environmental or lifestyle related, which means that, in theory, they can be altered, even prevented.

“There is always going to be some element of chance, but you can modify your chance, depending on your lifestyle and maybe other factors, which we don’t fully understand yet,” Dr. Gunter said.

The good news is that, when it comes to prevention, there are many ways to modify our behaviors – such as consuming fewer processed meats, going for a daily walk, or getting vaccinated against cancer-causing viruses – to improve our chances of living cancer free. And as scientists better understand more about what causes cancer, possibilities for prevention will only grow.

“There is a constant, slow growth [in knowledge] that is lowering the overall risk of cancer,” Dr. Brennan said. “We’re never going to eliminate cancer, but we will be able to control it as a disease.”

A version of this article first appeared on Medscape.com.

People with cancer are often desperate to know what caused their disease. Was it something they did? Something they could have prevented?

vitanovski/Thinkstock.com

In a recent analysis, experts estimated that about 40% of cancers can be explained by known, often modifiable risk factors. Smoking and obesity represent the primary drivers, though a host of other factors – germline mutations, alcohol, infections, or environmental pollutants like asbestos – contribute to cancer risk as well.

But what about the remaining 60% of cancers?

The study suggests that, although many of these cases likely have an underlying lifestyle or environmental component, experts still do not fully understand their origin story. And a small but significant number may simply be caused by chance.

Here’s what experts suspect those missing causes might be, and why they can be so difficult to confirm.
 

Possibility 1: Known risk factors contribute more than we realize

For certain factors, a straight line can be drawn to cancer.

Take smoking, for instance. Decades of research have helped scientists clearly delineate tobacco’s carcinogenic effects. Researchers have pinpointed a unique set of mutations in the tumors of smokers that can be seen when cells grown in a dish are exposed to the carcinogens present in tobacco.

In addition, experts have been able to collect robust data from epidemiologic studies on smoking prevalence as well as associated cancer risks and deaths, in large part because an individual’s lifetime tobacco exposure is fairly easy to measure.

“The evidence for smoking is incredibly consistent,” Paul Brennan, PhD, a cancer epidemiologist at the World Health Organization’s International Agency for Research on Cancer, said in an interview.

For other known risk factors, such as obesity and air pollution, many more questions than answers remain.

Because of the limitations in how such factors are measured, we are likely downplaying their effects, said Richard Martin, PhD, a professor of clinical epidemiology at the University of Bristol (England).

Take obesity. Excess body weight is associated with an increased risk of at least 13 cancers. Although risk estimates vary by study and cancer type, according to a global snapshot from 2012, being overweight or obese accounted for about 4% of all cancers worldwide – 1% in low-income countries and as high as 8% in high-income countries.

However, Dr. Brennan believes “we have underestimated the effect of obesity [on cancer].”

A key reason, he said, is most studies use body mass index to determine whether someone is overweight or obese, but BMI is a poor measure of body fat. BMI does not differentiate between fat and muscle, which means two people with the same height and weight can have the same BMI, even if one is an athlete who eats lean meats and vegetables while the other lives a sedentary life and consumes large quantities of processed foods and alcohol.

On top of that, studies often only calculate a person’s BMI once, and a single measurement can’t tell you how a person’s weight has fluctuated in recent years or across different stages of their life. However, recent analyses suggest that obesity status over time may be more relevant to cancer risk than one-off measures.

In addition, many studies now suggest that alterations to our gut microbes and high blood insulin level – often seen in people who are overweight or obese – may increase the risk of cancer and speed the growth of tumors.

When these additional factors are considered, the impact of excess body fat may ultimately play a much more significant role in cancer risk. In fact, according to Dr. Brennan, “if we estimate [the effects of obesity] properly, it might at some point become the main cause of cancer.”
 

Possibility 2: Environmental or lifestyle factors remain under the radar

Researchers have linked many substances we consume or are exposed to in our daily lives – air pollution, toxins from industrial waste, and highly processed foods – to cancer. But the extent or contribution of potential carcinogens in our surroundings, particularly those found almost everywhere at low levels, is still largely unknown.

One simple reason is the effects of many of these substances remain difficult to assess. For instance, it is much harder to study the impact of pollutants found in food or water, in which a given population will share similar exposure levels versus tobacco, where it is possible to compare a person who smokes a pack of cigarettes a day with a person who does not smoke.

“If you’ve got exposures that are ubiquitous, it can be difficult to discern their [individual] roles,” Dr. Martin said. “There are many causes that we [likely] don’t really know because everyone has been exposed.”

On the flip side, some carcinogenic substances that people encounter for limited periods might be missed if studies are not performed at the time of exposure.

“What’s in the body at age 40 may not reflect what you were exposed at age 5-10 on the playground or soccer field,” said Graham Colditz, MD, PhD, an epidemiologist and public health expert at Washington University, St. Louis. “The technology keeps changing so we can get better measures of what you’ve got exposure to today, but how that relates to 5, 10, 15 years ago is probably very variable.”

In addition, researchers have found that many carcinogens do not cause specific mutations in a cell’s DNA; rather, studies suggest that most carcinogens lead to cancer-promoting changes in cells, such as inflammation.

“We need to think of how potential carcinogens are causing cancer,” Dr. Brennan said. Instead of provoking mutations, potential carcinogens may use a “whole other kind of pathway.” When, for instance, inflammation becomes chronic, it may spur a cascade of events that ultimately leads to cancer.

Finally, not much is known about what causes cancers in low- and middle-income countries. Most of the research to date has been in high-income countries, such the United States, Australia, and parts of Europe.

“There’s a real lack of robust epidemiological studies in other parts of the world, Latin America, Africa, parts of Asia,” Marc Gunter, PhD, a molecular epidemiologist at the IARC, told this news organization.
 

Possibility 3: Some cancers occur by chance

When it comes to cancer risk, an element of chance may be at play. Cancer can occur in individuals who have very little exposure to known carcinogens or have no family history of cancer.

“We all know there are people who get cancer who eat very healthy diets, are never overweight, and never smoke,” Dr. Gunter said. “Then there are people on the other end of the extreme who don’t get cancer.”

But what fraction of cancers are attributable to chance?

A controversial 2017 study published in Science suggested that, based on the rate of cell turnover in healthy tissues in the lung, pancreas, and other parts of the body, only about one-third of cancers could be linked to environmental or genetic factors. The rest, the authors claimed, occurred because of random mutations that accumulated in a person’s DNA – in other words, bad luck.

That study brought on a flood of criticism from scientists who pointed to serious flaws in the work that led the researchers to significantly overestimate the share of chance-related cancers.

The actual proportion of cancers that occur by chance is much lower, according to Dr. Brennan. “If you look at international comparisons [of cancer rates] and take a conservative estimate, you see that maybe 10% or 15% of cancers are really chance.”

Whether some cancers are caused by bad luck or undiscovered risk factors remains an open question.

But the bottom line is many unknown causes of cancer are likely environmental or lifestyle related, which means that, in theory, they can be altered, even prevented.

“There is always going to be some element of chance, but you can modify your chance, depending on your lifestyle and maybe other factors, which we don’t fully understand yet,” Dr. Gunter said.

The good news is that, when it comes to prevention, there are many ways to modify our behaviors – such as consuming fewer processed meats, going for a daily walk, or getting vaccinated against cancer-causing viruses – to improve our chances of living cancer free. And as scientists better understand more about what causes cancer, possibilities for prevention will only grow.

“There is a constant, slow growth [in knowledge] that is lowering the overall risk of cancer,” Dr. Brennan said. “We’re never going to eliminate cancer, but we will be able to control it as a disease.”

A version of this article first appeared on Medscape.com.

On the basis of the patient's presentation and imaging results, the likely diagnosis is non–small cell cancer (NSCLC) of an adenocarcinoma subtype. NSCLC makes up about 80% of all lung cancer cases. Adenocarcinoma in particular is the most common type of lung cancer in the United States, accounting for about 40% of cases, and it is the most common histology among nonsmokers. Women are more likely to develop this subtype of NSCLC and are generally younger when they present with symptoms. This type of cancer arises from the bronchial mucosal glands and usually develops in a peripheral location within the lung. 

In the course of workup, immunohistochemical (IHC) analyses are used to identify tumor type and lineage (adenocarcinoma, squamous cell carcinoma, metastatic malignancy, or primary pleural mesothelioma). Separate IHC analyses are then used to guide treatment decisions, identifying whether ALK inhibitor therapy or programmed cell death protein ligand 1 (PD-L1) inhibitor therapy would be appropriate.

Tissue should also be conserved for molecular testing. NCCN guidelines advise that all patients with adenocarcinoma should be tested for EGFR mutations, and DNA mutational analysis is the preferred method for assessment. Patients should also undergo routine biomarker testing, with an eye toward ALK, RET, and ROS1 rearrangements, BRAF mutations, c-MET and exon 14 skipping mutations, and PD-L1 expression levels. For patients with metastatic NSCLC, PD-L1 IHC testing is recommended.

Most cases of lung cancer are diagnosed at a late stage, when symptoms have already begun to manifest. Of note, however, women with adenocarcinoma are more likely to present with localized disease. Treatment is largely influenced by the presence of targetable mutations. Among adenocarcinoma cases, the most common mutations are in the EGFR and KRAS genes.

For patients who are EGFR mutation positive (exon 10 deletion or L858R), osimertinib is the recommended first-line therapy. For patients who are positive for the EGFR exon 20 insertion mutation, initial systemic therapy options for adenocarcinoma are appropriate; the preferred regimen being pembrolizumab-carboplatin-pemetrexed if there are no contraindications to programmed cell death protein 1 (PD-1) or PD-L1 inhibitors.

KRAS mutations, unlike EGFR mutations, are associated with smoking. Because overlapping targetable alterations are uncommon, identification of KRAS mutations suggests that these patients will not benefit from additional molecular testing. Again, initial systemic therapy options for adenocarcinoma are appropriate, but the presence of KRAS mutation predicts a poor response to EGFR tyrosine kinase inhibitors. The FDA approved a KRAS inhibitor in June 2021 and immune checkpoint inhibitors appear to be beneficial in this population.

Maurie Markman, MD, President, Department of Medical Oncology, Cancer Treatment Centers of America.

Maurie Markman, MD, has disclosed the following relevant financial relationships:

Serve(d) as a director, officer, partner, employee, advisor, consultant, or trustee for: Merck
Serve(d) as a speaker or a member of a speakers bureau for: AstraZeneca; Novis; Glaxo Smith Kline
Received research grant from: AstraZeneca; Novis; GSK; Merck

On the basis of the patient's presentation and imaging results, the likely diagnosis is non–small cell cancer (NSCLC) of an adenocarcinoma subtype. NSCLC makes up about 80% of all lung cancer cases. Adenocarcinoma in particular is the most common type of lung cancer in the United States, accounting for about 40% of cases, and it is the most common histology among nonsmokers. Women are more likely to develop this subtype of NSCLC and are generally younger when they present with symptoms. This type of cancer arises from the bronchial mucosal glands and usually develops in a peripheral location within the lung. 

In the course of workup, immunohistochemical (IHC) analyses are used to identify tumor type and lineage (adenocarcinoma, squamous cell carcinoma, metastatic malignancy, or primary pleural mesothelioma). Separate IHC analyses are then used to guide treatment decisions, identifying whether ALK inhibitor therapy or programmed cell death protein ligand 1 (PD-L1) inhibitor therapy would be appropriate.

Tissue should also be conserved for molecular testing. NCCN guidelines advise that all patients with adenocarcinoma should be tested for EGFR mutations, and DNA mutational analysis is the preferred method for assessment. Patients should also undergo routine biomarker testing, with an eye toward ALK, RET, and ROS1 rearrangements, BRAF mutations, c-MET and exon 14 skipping mutations, and PD-L1 expression levels. For patients with metastatic NSCLC, PD-L1 IHC testing is recommended.

Most cases of lung cancer are diagnosed at a late stage, when symptoms have already begun to manifest. Of note, however, women with adenocarcinoma are more likely to present with localized disease. Treatment is largely influenced by the presence of targetable mutations. Among adenocarcinoma cases, the most common mutations are in the EGFR and KRAS genes.

For patients who are EGFR mutation positive (exon 10 deletion or L858R), osimertinib is the recommended first-line therapy. For patients who are positive for the EGFR exon 20 insertion mutation, initial systemic therapy options for adenocarcinoma are appropriate; the preferred regimen being pembrolizumab-carboplatin-pemetrexed if there are no contraindications to programmed cell death protein 1 (PD-1) or PD-L1 inhibitors.

KRAS mutations, unlike EGFR mutations, are associated with smoking. Because overlapping targetable alterations are uncommon, identification of KRAS mutations suggests that these patients will not benefit from additional molecular testing. Again, initial systemic therapy options for adenocarcinoma are appropriate, but the presence of KRAS mutation predicts a poor response to EGFR tyrosine kinase inhibitors. The FDA approved a KRAS inhibitor in June 2021 and immune checkpoint inhibitors appear to be beneficial in this population.

Maurie Markman, MD, President, Department of Medical Oncology, Cancer Treatment Centers of America.

Maurie Markman, MD, has disclosed the following relevant financial relationships:

Serve(d) as a director, officer, partner, employee, advisor, consultant, or trustee for: Merck
Serve(d) as a speaker or a member of a speakers bureau for: AstraZeneca; Novis; Glaxo Smith Kline
Received research grant from: AstraZeneca; Novis; GSK; Merck

On the basis of the patient's presentation and imaging results, the likely diagnosis is non–small cell cancer (NSCLC) of an adenocarcinoma subtype. NSCLC makes up about 80% of all lung cancer cases. Adenocarcinoma in particular is the most common type of lung cancer in the United States, accounting for about 40% of cases, and it is the most common histology among nonsmokers. Women are more likely to develop this subtype of NSCLC and are generally younger when they present with symptoms. This type of cancer arises from the bronchial mucosal glands and usually develops in a peripheral location within the lung. 

In the course of workup, immunohistochemical (IHC) analyses are used to identify tumor type and lineage (adenocarcinoma, squamous cell carcinoma, metastatic malignancy, or primary pleural mesothelioma). Separate IHC analyses are then used to guide treatment decisions, identifying whether ALK inhibitor therapy or programmed cell death protein ligand 1 (PD-L1) inhibitor therapy would be appropriate.

Tissue should also be conserved for molecular testing. NCCN guidelines advise that all patients with adenocarcinoma should be tested for EGFR mutations, and DNA mutational analysis is the preferred method for assessment. Patients should also undergo routine biomarker testing, with an eye toward ALK, RET, and ROS1 rearrangements, BRAF mutations, c-MET and exon 14 skipping mutations, and PD-L1 expression levels. For patients with metastatic NSCLC, PD-L1 IHC testing is recommended.

Most cases of lung cancer are diagnosed at a late stage, when symptoms have already begun to manifest. Of note, however, women with adenocarcinoma are more likely to present with localized disease. Treatment is largely influenced by the presence of targetable mutations. Among adenocarcinoma cases, the most common mutations are in the EGFR and KRAS genes.

For patients who are EGFR mutation positive (exon 10 deletion or L858R), osimertinib is the recommended first-line therapy. For patients who are positive for the EGFR exon 20 insertion mutation, initial systemic therapy options for adenocarcinoma are appropriate; the preferred regimen being pembrolizumab-carboplatin-pemetrexed if there are no contraindications to programmed cell death protein 1 (PD-1) or PD-L1 inhibitors.

KRAS mutations, unlike EGFR mutations, are associated with smoking. Because overlapping targetable alterations are uncommon, identification of KRAS mutations suggests that these patients will not benefit from additional molecular testing. Again, initial systemic therapy options for adenocarcinoma are appropriate, but the presence of KRAS mutation predicts a poor response to EGFR tyrosine kinase inhibitors. The FDA approved a KRAS inhibitor in June 2021 and immune checkpoint inhibitors appear to be beneficial in this population.

Maurie Markman, MD, President, Department of Medical Oncology, Cancer Treatment Centers of America.

Maurie Markman, MD, has disclosed the following relevant financial relationships:

Serve(d) as a director, officer, partner, employee, advisor, consultant, or trustee for: Merck
Serve(d) as a speaker or a member of a speakers bureau for: AstraZeneca; Novis; Glaxo Smith Kline
Received research grant from: AstraZeneca; Novis; GSK; Merck

According to the Centers for Disease Control and Prevention, lung cancer is the third-most common cancer in the United States and the leading cause of cancer deaths in both men and women. Approximately, 150,000 Americans die every year from this disease.

For many years, no effective screening tests were available for lung cancer. This has changed with the advent of low-dose CT scanning as a screening method. In fact, it has been shown that low-dose CT scan screening can reduce lung cancer deaths by 20%-30% in high-risk populations.

In the United States, low-dose CT scan screening for lung cancer has largely become the norm. In July 2021, CHEST released new clinical guidelines. These guidelines cover 18 evidence-based recommendations as well as inclusion of further evidence regarding the benefits, risks, and use of CT screening.

In doing the risk assessment of low-dose CT scan as a method of lung cancer screening, meta-analyses were performed on evidence obtained through a literature search using PubMed, Embase, and the Cochrane Library. It was concluded that the benefits outweigh the risks as a method of lung cancer screening and can be utilized in reducing lung cancer deaths.

Low-dose CT scan screening was recommended for the following patients:

• Asymptomatic individuals aged 55-77 years with a history of smoking 30 or more pack-years. (This includes those who continue to smoke or who have quit in the previous 15 years. Annual screening is advised.)
• Asymptomatic individuals aged 55-80 years with a history of smoking 20-30 pack-years who either continue to smoke or have quit in the previous 15 years.
• For asymptomatic individuals who do not meet the above criteria but are predicted to benefit based on life-year gained calculations.

Don’t screen these patients

CT scan screening should not be performed on any person who does not meet any of the above three criteria.

Additionally, if a person has significant comorbidities that would limit their life expectancy, it is recommended not to do CT scan screening. Symptomatic patients should have appropriate diagnostic testing rather than screening.

Additional recommendations from the updated guidelines include developing appropriate counseling strategies as well as deciding what constitutes a positive test.

A positive test should be anything that warrants further evaluation rather than a return to annual screening. It was also advised that overtreatment strategies should be implemented. Additionally, smoking cessation treatment should be provided.

CHEST suggested undertaking a comprehensive approach involving multiple specialists including pulmonologists, radiologists, oncologists, etc. Strategies to ensure compliance with annual screening should also be devised, the guidelines say.
 

USPSTF’s updated guidelines

It should be noted that the U.S. Preventative Task Force released their own set of updated guidelines in March 2021. In these guidelines, the age at which lung cancer screening should be started was lowered from 55 years to 50 years.

Also, the USPSTF lowered the minimum required smoking history in order to be screened from 30 to 20 pack-years. Their purpose for doing this was to include more high-risk women as well as minorities.

With the changes, 14.5 million individuals living in the United States would be eligible for lung cancer screening by low-dose CT scan, an increase of 6.5 million people, compared with the previous guidelines.

While only small differences exist between the set of guidelines issued by CHEST and the ones issues by the USPSTF, lung cancer screening is still largely underutilized.

One of the barriers to screening may be patients’ lacking insurance coverage for it. As physicians, we need to advocate for these screening tools to be covered.

Other barriers include lack of patient knowledge regarding low-dose CT scans as a screening tool, patient time, and patient visits with their doctors being too short.
 

Key message

Part of the duties of physicians is to give our patients the best information. We can reduce lung cancer mortality in high risk patients by performing annual low-dose CT scans.

Whichever set of guidelines we chose to follow, we fail our patients if we don’t follow either set of them. The evidence is clear that a low-dose CT scan is a valuable screening tool to add to our practice of medicine.

Dr. Girgis practices family medicine in South River, N.J., and is a clinical assistant professor of family medicine at Robert Wood Johnson Medical School, New Brunswick, N.J. You can contact her at fpnews@mdedge.com.

According to the Centers for Disease Control and Prevention, lung cancer is the third-most common cancer in the United States and the leading cause of cancer deaths in both men and women. Approximately, 150,000 Americans die every year from this disease.

For many years, no effective screening tests were available for lung cancer. This has changed with the advent of low-dose CT scanning as a screening method. In fact, it has been shown that low-dose CT scan screening can reduce lung cancer deaths by 20%-30% in high-risk populations.

In the United States, low-dose CT scan screening for lung cancer has largely become the norm. In July 2021, CHEST released new clinical guidelines. These guidelines cover 18 evidence-based recommendations as well as inclusion of further evidence regarding the benefits, risks, and use of CT screening.

In doing the risk assessment of low-dose CT scan as a method of lung cancer screening, meta-analyses were performed on evidence obtained through a literature search using PubMed, Embase, and the Cochrane Library. It was concluded that the benefits outweigh the risks as a method of lung cancer screening and can be utilized in reducing lung cancer deaths.

Low-dose CT scan screening was recommended for the following patients:

• Asymptomatic individuals aged 55-77 years with a history of smoking 30 or more pack-years. (This includes those who continue to smoke or who have quit in the previous 15 years. Annual screening is advised.)
• Asymptomatic individuals aged 55-80 years with a history of smoking 20-30 pack-years who either continue to smoke or have quit in the previous 15 years.
• For asymptomatic individuals who do not meet the above criteria but are predicted to benefit based on life-year gained calculations.

Don’t screen these patients

CT scan screening should not be performed on any person who does not meet any of the above three criteria.

Additionally, if a person has significant comorbidities that would limit their life expectancy, it is recommended not to do CT scan screening. Symptomatic patients should have appropriate diagnostic testing rather than screening.

Additional recommendations from the updated guidelines include developing appropriate counseling strategies as well as deciding what constitutes a positive test.

A positive test should be anything that warrants further evaluation rather than a return to annual screening. It was also advised that overtreatment strategies should be implemented. Additionally, smoking cessation treatment should be provided.

CHEST suggested undertaking a comprehensive approach involving multiple specialists including pulmonologists, radiologists, oncologists, etc. Strategies to ensure compliance with annual screening should also be devised, the guidelines say.
 

USPSTF’s updated guidelines

It should be noted that the U.S. Preventative Task Force released their own set of updated guidelines in March 2021. In these guidelines, the age at which lung cancer screening should be started was lowered from 55 years to 50 years.

Also, the USPSTF lowered the minimum required smoking history in order to be screened from 30 to 20 pack-years. Their purpose for doing this was to include more high-risk women as well as minorities.

With the changes, 14.5 million individuals living in the United States would be eligible for lung cancer screening by low-dose CT scan, an increase of 6.5 million people, compared with the previous guidelines.

While only small differences exist between the set of guidelines issued by CHEST and the ones issues by the USPSTF, lung cancer screening is still largely underutilized.

One of the barriers to screening may be patients’ lacking insurance coverage for it. As physicians, we need to advocate for these screening tools to be covered.

Other barriers include lack of patient knowledge regarding low-dose CT scans as a screening tool, patient time, and patient visits with their doctors being too short.
 

Key message

Part of the duties of physicians is to give our patients the best information. We can reduce lung cancer mortality in high risk patients by performing annual low-dose CT scans.

Whichever set of guidelines we chose to follow, we fail our patients if we don’t follow either set of them. The evidence is clear that a low-dose CT scan is a valuable screening tool to add to our practice of medicine.

Dr. Girgis practices family medicine in South River, N.J., and is a clinical assistant professor of family medicine at Robert Wood Johnson Medical School, New Brunswick, N.J. You can contact her at fpnews@mdedge.com.

According to the Centers for Disease Control and Prevention, lung cancer is the third-most common cancer in the United States and the leading cause of cancer deaths in both men and women. Approximately, 150,000 Americans die every year from this disease.

For many years, no effective screening tests were available for lung cancer. This has changed with the advent of low-dose CT scanning as a screening method. In fact, it has been shown that low-dose CT scan screening can reduce lung cancer deaths by 20%-30% in high-risk populations.

In the United States, low-dose CT scan screening for lung cancer has largely become the norm. In July 2021, CHEST released new clinical guidelines. These guidelines cover 18 evidence-based recommendations as well as inclusion of further evidence regarding the benefits, risks, and use of CT screening.

In doing the risk assessment of low-dose CT scan as a method of lung cancer screening, meta-analyses were performed on evidence obtained through a literature search using PubMed, Embase, and the Cochrane Library. It was concluded that the benefits outweigh the risks as a method of lung cancer screening and can be utilized in reducing lung cancer deaths.

Low-dose CT scan screening was recommended for the following patients:

• Asymptomatic individuals aged 55-77 years with a history of smoking 30 or more pack-years. (This includes those who continue to smoke or who have quit in the previous 15 years. Annual screening is advised.)
• Asymptomatic individuals aged 55-80 years with a history of smoking 20-30 pack-years who either continue to smoke or have quit in the previous 15 years.
• For asymptomatic individuals who do not meet the above criteria but are predicted to benefit based on life-year gained calculations.

Don’t screen these patients

CT scan screening should not be performed on any person who does not meet any of the above three criteria.

Additionally, if a person has significant comorbidities that would limit their life expectancy, it is recommended not to do CT scan screening. Symptomatic patients should have appropriate diagnostic testing rather than screening.

Additional recommendations from the updated guidelines include developing appropriate counseling strategies as well as deciding what constitutes a positive test.

A positive test should be anything that warrants further evaluation rather than a return to annual screening. It was also advised that overtreatment strategies should be implemented. Additionally, smoking cessation treatment should be provided.

CHEST suggested undertaking a comprehensive approach involving multiple specialists including pulmonologists, radiologists, oncologists, etc. Strategies to ensure compliance with annual screening should also be devised, the guidelines say.
 

USPSTF’s updated guidelines

It should be noted that the U.S. Preventative Task Force released their own set of updated guidelines in March 2021. In these guidelines, the age at which lung cancer screening should be started was lowered from 55 years to 50 years.

Also, the USPSTF lowered the minimum required smoking history in order to be screened from 30 to 20 pack-years. Their purpose for doing this was to include more high-risk women as well as minorities.

With the changes, 14.5 million individuals living in the United States would be eligible for lung cancer screening by low-dose CT scan, an increase of 6.5 million people, compared with the previous guidelines.

While only small differences exist between the set of guidelines issued by CHEST and the ones issues by the USPSTF, lung cancer screening is still largely underutilized.

One of the barriers to screening may be patients’ lacking insurance coverage for it. As physicians, we need to advocate for these screening tools to be covered.

Other barriers include lack of patient knowledge regarding low-dose CT scans as a screening tool, patient time, and patient visits with their doctors being too short.
 

Key message

Part of the duties of physicians is to give our patients the best information. We can reduce lung cancer mortality in high risk patients by performing annual low-dose CT scans.

Whichever set of guidelines we chose to follow, we fail our patients if we don’t follow either set of them. The evidence is clear that a low-dose CT scan is a valuable screening tool to add to our practice of medicine.

Dr. Girgis practices family medicine in South River, N.J., and is a clinical assistant professor of family medicine at Robert Wood Johnson Medical School, New Brunswick, N.J. You can contact her at fpnews@mdedge.com.

On a recent Friday, oncologist Christine Berg, MD, devoted 3 hours to a webinar about electrification of heavy- and medium-duty trucks in Maryland.

It’s not the way most cancer specialists choose to spend their time. But Dr. Berg, who is board certified in medical oncology, radiation oncology, and internal medicine, has made air pollution her current focus. Through organizations such as the Public Employees for Environmental Responsibility, she is working to raise awareness of the huge impact it can have on cancer.

“I think oncologists can make a difference,” she said.

That’s why Dr. Berg took a keen interest in a recent study by ProPublica, the nonprofit journalism organization, that identified previously ignored “hot spots of cancer-causing air.” While the ProPublica report gives an incomplete picture of airborne carcinogens, it puts an important spotlight on industrial air pollution, Dr. Berg and other experts say.

Relying on data from the Environmental Protection Agency’s Risk-Screening Environmental Indicators (RSEI), ProPublica researchers estimated the effects of industrial air pollution around the country and found problems the EPA overlooked, they reported. “The EPA collects data on each individual facility, but it doesn’t consider the excess cancer risk from all of the facilities’ combined emissions,” reporter Lylla Younes and colleagues wrote. “ProPublica did.”

The ProPublica team produced a map of cancer-causing industrial air pollution hot spots. They estimated that 256,000 people in the United States live in areas where incidences of cancer caused by air pollution exceed the EPA’s upper limit of acceptable risk.

While some of the spots are scattered around the country, they are concentrated along the Gulf Coast of Texas and Louisiana. For example, near the Equistar Chemicals Bayport Chemical Plant in Pasadena, Texas, ProPublica calculated the increased risk of cancer at 1 in 220, “46 times the EPA’s acceptable risk.” (The agency defines an acceptable risk as less than a 1 in 10,000 chance of developing cancer.)

Almost all the hot spots with the highest level of risk are in southern United States “known for having weaker environmental regulations,” the report said.

The researchers also identified race as a risk factor. In predominantly Black census tracts, they estimated the risk from toxic air pollution is more than double the risk in predominantly White census tracts. It attributed this pattern to deliberate policies of redlining that segregated neighborhoods and to zoning ordinances that encouraged industry in communities of color.
 

Measuring risk not straightforward

In response to a query from this news organization, an EPA spokesperson provided a statement saying the RSEI data are not intended for the purpose used by ProPublica. “RSEI does not provide a risk assessment (e.g., excess cancer case estimates),” the statement said. The RSEI data are poorly suited to this purpose because they use “worst-case assumptions about toxicity and potential exposure where data are lacking, and also use simplifying assumptions to reduce the complexity of the calculations,” the statement said.

Instead, the data are meant as a kind of index to compare one place to another, or show changes over time, the agency said. In this way, it can prompt regulators to investigate further. “A more refined assessment is required before any conclusions about health impacts can be drawn.” The agency is working on just such a refined approach, per the EPA statement.

That’s not just bureaucratic stonewalling, said Stan Meiberg, PhD, MA, a former EPA official and director of graduate studies in sustainability at Wake Forest University in Winston-Salem, N.C. “To say that you can speak with great precision, that the risk of individuals getting cancer is 1 in 100, may be a little overstating the date on which that statement is based.”

Risk estimates are improving as citizens gain access to more sophisticated monitoring devices, he said. And the primary point of the ProPublica report, that the EPA has underestimated risk by looking at individual sources of pollution rather than combining them, is not an original one, Dr. Meiberg said. “This is an issue that’s been kicking around for quite some time.”

Still, it’s one that demands attention. EPA regulations have succeeded in reducing the overall risk from industrial air pollution over the past few decades. “But there remain areas of particular geographic concentrations,” he said. “And the ProPublica article hit two of them, which have been the subject of discussion for many years, the Houston Ship Channel area and the Baton Rouge to New Orleans industrial corridor where you have a significant proportion of all the chemical petrochemical industry in the United States.”

Improvements in containment of the pollutants, and changes to the industrial processes that produce them, can also help reduce exposure. These changes should occur in the context of dialogue within the communities exposed to the pollution, Dr. Meiberg said.
 

The role of cancer-causing airborne particulate matter

But even if measures are perfectly implemented, Joan Schiller, MD, will not breathe easy. An adjunct professor of oncology at the University of Virginia in Charlottesville, Dr. Schiller has researched the role of airborne particulate matter in causing cancer, a correlation barely mentioned in the ProPublica analysis, she pointed out.

Particulate matter contains a wide range of toxic substances, she said. Researchers have focused on particles 2.5 microns in diameter, or PM 2.5. Some studies have indicated that it’s responsible for one in seven deaths from lung cancer, Dr. Schiller said. “Air pollution also causes lung cancer in never smokers, people who’ve never smoked, not just in smokers.”

Power plants and automobile traffic may be more significant sources of PM 2.5 than industry, and wildfires have recently emerged as increasingly important source, a result of climate change and poor forest management, she said.

PM 2.5 doesn’t affect just lung cancer, said Alexandra White, PhD, an investigator at the National Institute of Environmental Health Sciences in Research Triangle Park, N.C. “My work, as well as work of others, is increasingly suggesting that air pollution is also related to breast cancer risk, in particular, air pollution that is arising from traffic related forces.” And more research is needed on other cancers, she said. “I think that the lack of findings of other cancer sites reflects a lack of study.”

Other pollutants not analyzed in the ProPublica report are also correlated to cancer risk. In a recent meta-analysis, researcher Stephan Gabet, PhD, PharmD, and colleagues at the University of Grenoble, France, estimated that 3.15% of new breast cancer cases in that country could be attributed to nitrogen dioxide and 2.15% to PM 10.

Sources of nitrogen dioxide, PM 2.5, and PM 10 in France include automobile traffic, inefficient wood-burning stoves, and coal-burning power plants in neighboring countries, Dr. Gabet said.

A good approach to reducing pollution from road traffic is the implementation of low-emission zones that prohibit the most polluting vehicles, he said. But a 2019 United Kingdom government study found that brake wear, tire wear, and road surface wear account for 72% of the PM 10 and 60% of the PM 2.5 pollution from road traffic, suggesting that a transition to electric vehicles won’t fix the problem. Better yet, is “the promotion of active modes like walking, cycling, etc., because like this, you can bring additional health gains due to the increase in physical activity,” he said.

Oncologists can help their patients reduce their exposure to air pollution, Dr. Schiller said. “If you have lung cancer, air pollution will hasten your demise. It makes you sicker. Oncologists should be telling their patients about this and advising them to move away from air pollution if possible, and also making sure they know to monitor the health of the air.”

On days when air pollution is high, patients may want to avoid exercising outdoors, or stay indoors altogether, Dr. Berg said. Air purifiers and N95 masks may also help.

And physicians can make a difference by speaking out in their communities, Dr. Schiller said. She is inviting oncologists to join a new group, Oncologists Understanding for Climate and Health. Through this group or on their own, oncologists can speak to their local legislatures or city councils in support of measures to reduce pollution, she said. “Doctors are trusted messengers.”

Dr. Berg disclosed affiliations with Grail, Mercy BioAnalytics and Lucid Diagnostics.

On a recent Friday, oncologist Christine Berg, MD, devoted 3 hours to a webinar about electrification of heavy- and medium-duty trucks in Maryland.

It’s not the way most cancer specialists choose to spend their time. But Dr. Berg, who is board certified in medical oncology, radiation oncology, and internal medicine, has made air pollution her current focus. Through organizations such as the Public Employees for Environmental Responsibility, she is working to raise awareness of the huge impact it can have on cancer.

“I think oncologists can make a difference,” she said.

That’s why Dr. Berg took a keen interest in a recent study by ProPublica, the nonprofit journalism organization, that identified previously ignored “hot spots of cancer-causing air.” While the ProPublica report gives an incomplete picture of airborne carcinogens, it puts an important spotlight on industrial air pollution, Dr. Berg and other experts say.

Relying on data from the Environmental Protection Agency’s Risk-Screening Environmental Indicators (RSEI), ProPublica researchers estimated the effects of industrial air pollution around the country and found problems the EPA overlooked, they reported. “The EPA collects data on each individual facility, but it doesn’t consider the excess cancer risk from all of the facilities’ combined emissions,” reporter Lylla Younes and colleagues wrote. “ProPublica did.”

The ProPublica team produced a map of cancer-causing industrial air pollution hot spots. They estimated that 256,000 people in the United States live in areas where incidences of cancer caused by air pollution exceed the EPA’s upper limit of acceptable risk.

While some of the spots are scattered around the country, they are concentrated along the Gulf Coast of Texas and Louisiana. For example, near the Equistar Chemicals Bayport Chemical Plant in Pasadena, Texas, ProPublica calculated the increased risk of cancer at 1 in 220, “46 times the EPA’s acceptable risk.” (The agency defines an acceptable risk as less than a 1 in 10,000 chance of developing cancer.)

Almost all the hot spots with the highest level of risk are in southern United States “known for having weaker environmental regulations,” the report said.

The researchers also identified race as a risk factor. In predominantly Black census tracts, they estimated the risk from toxic air pollution is more than double the risk in predominantly White census tracts. It attributed this pattern to deliberate policies of redlining that segregated neighborhoods and to zoning ordinances that encouraged industry in communities of color.
 

Measuring risk not straightforward

In response to a query from this news organization, an EPA spokesperson provided a statement saying the RSEI data are not intended for the purpose used by ProPublica. “RSEI does not provide a risk assessment (e.g., excess cancer case estimates),” the statement said. The RSEI data are poorly suited to this purpose because they use “worst-case assumptions about toxicity and potential exposure where data are lacking, and also use simplifying assumptions to reduce the complexity of the calculations,” the statement said.

Instead, the data are meant as a kind of index to compare one place to another, or show changes over time, the agency said. In this way, it can prompt regulators to investigate further. “A more refined assessment is required before any conclusions about health impacts can be drawn.” The agency is working on just such a refined approach, per the EPA statement.

That’s not just bureaucratic stonewalling, said Stan Meiberg, PhD, MA, a former EPA official and director of graduate studies in sustainability at Wake Forest University in Winston-Salem, N.C. “To say that you can speak with great precision, that the risk of individuals getting cancer is 1 in 100, may be a little overstating the date on which that statement is based.”

Risk estimates are improving as citizens gain access to more sophisticated monitoring devices, he said. And the primary point of the ProPublica report, that the EPA has underestimated risk by looking at individual sources of pollution rather than combining them, is not an original one, Dr. Meiberg said. “This is an issue that’s been kicking around for quite some time.”

Still, it’s one that demands attention. EPA regulations have succeeded in reducing the overall risk from industrial air pollution over the past few decades. “But there remain areas of particular geographic concentrations,” he said. “And the ProPublica article hit two of them, which have been the subject of discussion for many years, the Houston Ship Channel area and the Baton Rouge to New Orleans industrial corridor where you have a significant proportion of all the chemical petrochemical industry in the United States.”

Improvements in containment of the pollutants, and changes to the industrial processes that produce them, can also help reduce exposure. These changes should occur in the context of dialogue within the communities exposed to the pollution, Dr. Meiberg said.
 

The role of cancer-causing airborne particulate matter

But even if measures are perfectly implemented, Joan Schiller, MD, will not breathe easy. An adjunct professor of oncology at the University of Virginia in Charlottesville, Dr. Schiller has researched the role of airborne particulate matter in causing cancer, a correlation barely mentioned in the ProPublica analysis, she pointed out.

Particulate matter contains a wide range of toxic substances, she said. Researchers have focused on particles 2.5 microns in diameter, or PM 2.5. Some studies have indicated that it’s responsible for one in seven deaths from lung cancer, Dr. Schiller said. “Air pollution also causes lung cancer in never smokers, people who’ve never smoked, not just in smokers.”

Power plants and automobile traffic may be more significant sources of PM 2.5 than industry, and wildfires have recently emerged as increasingly important source, a result of climate change and poor forest management, she said.

PM 2.5 doesn’t affect just lung cancer, said Alexandra White, PhD, an investigator at the National Institute of Environmental Health Sciences in Research Triangle Park, N.C. “My work, as well as work of others, is increasingly suggesting that air pollution is also related to breast cancer risk, in particular, air pollution that is arising from traffic related forces.” And more research is needed on other cancers, she said. “I think that the lack of findings of other cancer sites reflects a lack of study.”

Other pollutants not analyzed in the ProPublica report are also correlated to cancer risk. In a recent meta-analysis, researcher Stephan Gabet, PhD, PharmD, and colleagues at the University of Grenoble, France, estimated that 3.15% of new breast cancer cases in that country could be attributed to nitrogen dioxide and 2.15% to PM 10.

Sources of nitrogen dioxide, PM 2.5, and PM 10 in France include automobile traffic, inefficient wood-burning stoves, and coal-burning power plants in neighboring countries, Dr. Gabet said.

A good approach to reducing pollution from road traffic is the implementation of low-emission zones that prohibit the most polluting vehicles, he said. But a 2019 United Kingdom government study found that brake wear, tire wear, and road surface wear account for 72% of the PM 10 and 60% of the PM 2.5 pollution from road traffic, suggesting that a transition to electric vehicles won’t fix the problem. Better yet, is “the promotion of active modes like walking, cycling, etc., because like this, you can bring additional health gains due to the increase in physical activity,” he said.

Oncologists can help their patients reduce their exposure to air pollution, Dr. Schiller said. “If you have lung cancer, air pollution will hasten your demise. It makes you sicker. Oncologists should be telling their patients about this and advising them to move away from air pollution if possible, and also making sure they know to monitor the health of the air.”

On days when air pollution is high, patients may want to avoid exercising outdoors, or stay indoors altogether, Dr. Berg said. Air purifiers and N95 masks may also help.

And physicians can make a difference by speaking out in their communities, Dr. Schiller said. She is inviting oncologists to join a new group, Oncologists Understanding for Climate and Health. Through this group or on their own, oncologists can speak to their local legislatures or city councils in support of measures to reduce pollution, she said. “Doctors are trusted messengers.”

Dr. Berg disclosed affiliations with Grail, Mercy BioAnalytics and Lucid Diagnostics.

On a recent Friday, oncologist Christine Berg, MD, devoted 3 hours to a webinar about electrification of heavy- and medium-duty trucks in Maryland.

It’s not the way most cancer specialists choose to spend their time. But Dr. Berg, who is board certified in medical oncology, radiation oncology, and internal medicine, has made air pollution her current focus. Through organizations such as the Public Employees for Environmental Responsibility, she is working to raise awareness of the huge impact it can have on cancer.

“I think oncologists can make a difference,” she said.

That’s why Dr. Berg took a keen interest in a recent study by ProPublica, the nonprofit journalism organization, that identified previously ignored “hot spots of cancer-causing air.” While the ProPublica report gives an incomplete picture of airborne carcinogens, it puts an important spotlight on industrial air pollution, Dr. Berg and other experts say.

Relying on data from the Environmental Protection Agency’s Risk-Screening Environmental Indicators (RSEI), ProPublica researchers estimated the effects of industrial air pollution around the country and found problems the EPA overlooked, they reported. “The EPA collects data on each individual facility, but it doesn’t consider the excess cancer risk from all of the facilities’ combined emissions,” reporter Lylla Younes and colleagues wrote. “ProPublica did.”

The ProPublica team produced a map of cancer-causing industrial air pollution hot spots. They estimated that 256,000 people in the United States live in areas where incidences of cancer caused by air pollution exceed the EPA’s upper limit of acceptable risk.

While some of the spots are scattered around the country, they are concentrated along the Gulf Coast of Texas and Louisiana. For example, near the Equistar Chemicals Bayport Chemical Plant in Pasadena, Texas, ProPublica calculated the increased risk of cancer at 1 in 220, “46 times the EPA’s acceptable risk.” (The agency defines an acceptable risk as less than a 1 in 10,000 chance of developing cancer.)

Almost all the hot spots with the highest level of risk are in southern United States “known for having weaker environmental regulations,” the report said.

The researchers also identified race as a risk factor. In predominantly Black census tracts, they estimated the risk from toxic air pollution is more than double the risk in predominantly White census tracts. It attributed this pattern to deliberate policies of redlining that segregated neighborhoods and to zoning ordinances that encouraged industry in communities of color.
 

Measuring risk not straightforward

In response to a query from this news organization, an EPA spokesperson provided a statement saying the RSEI data are not intended for the purpose used by ProPublica. “RSEI does not provide a risk assessment (e.g., excess cancer case estimates),” the statement said. The RSEI data are poorly suited to this purpose because they use “worst-case assumptions about toxicity and potential exposure where data are lacking, and also use simplifying assumptions to reduce the complexity of the calculations,” the statement said.

Instead, the data are meant as a kind of index to compare one place to another, or show changes over time, the agency said. In this way, it can prompt regulators to investigate further. “A more refined assessment is required before any conclusions about health impacts can be drawn.” The agency is working on just such a refined approach, per the EPA statement.

That’s not just bureaucratic stonewalling, said Stan Meiberg, PhD, MA, a former EPA official and director of graduate studies in sustainability at Wake Forest University in Winston-Salem, N.C. “To say that you can speak with great precision, that the risk of individuals getting cancer is 1 in 100, may be a little overstating the date on which that statement is based.”

Risk estimates are improving as citizens gain access to more sophisticated monitoring devices, he said. And the primary point of the ProPublica report, that the EPA has underestimated risk by looking at individual sources of pollution rather than combining them, is not an original one, Dr. Meiberg said. “This is an issue that’s been kicking around for quite some time.”

Still, it’s one that demands attention. EPA regulations have succeeded in reducing the overall risk from industrial air pollution over the past few decades. “But there remain areas of particular geographic concentrations,” he said. “And the ProPublica article hit two of them, which have been the subject of discussion for many years, the Houston Ship Channel area and the Baton Rouge to New Orleans industrial corridor where you have a significant proportion of all the chemical petrochemical industry in the United States.”

Improvements in containment of the pollutants, and changes to the industrial processes that produce them, can also help reduce exposure. These changes should occur in the context of dialogue within the communities exposed to the pollution, Dr. Meiberg said.
 

The role of cancer-causing airborne particulate matter

But even if measures are perfectly implemented, Joan Schiller, MD, will not breathe easy. An adjunct professor of oncology at the University of Virginia in Charlottesville, Dr. Schiller has researched the role of airborne particulate matter in causing cancer, a correlation barely mentioned in the ProPublica analysis, she pointed out.

Particulate matter contains a wide range of toxic substances, she said. Researchers have focused on particles 2.5 microns in diameter, or PM 2.5. Some studies have indicated that it’s responsible for one in seven deaths from lung cancer, Dr. Schiller said. “Air pollution also causes lung cancer in never smokers, people who’ve never smoked, not just in smokers.”

Power plants and automobile traffic may be more significant sources of PM 2.5 than industry, and wildfires have recently emerged as increasingly important source, a result of climate change and poor forest management, she said.

PM 2.5 doesn’t affect just lung cancer, said Alexandra White, PhD, an investigator at the National Institute of Environmental Health Sciences in Research Triangle Park, N.C. “My work, as well as work of others, is increasingly suggesting that air pollution is also related to breast cancer risk, in particular, air pollution that is arising from traffic related forces.” And more research is needed on other cancers, she said. “I think that the lack of findings of other cancer sites reflects a lack of study.”

Other pollutants not analyzed in the ProPublica report are also correlated to cancer risk. In a recent meta-analysis, researcher Stephan Gabet, PhD, PharmD, and colleagues at the University of Grenoble, France, estimated that 3.15% of new breast cancer cases in that country could be attributed to nitrogen dioxide and 2.15% to PM 10.

Sources of nitrogen dioxide, PM 2.5, and PM 10 in France include automobile traffic, inefficient wood-burning stoves, and coal-burning power plants in neighboring countries, Dr. Gabet said.

A good approach to reducing pollution from road traffic is the implementation of low-emission zones that prohibit the most polluting vehicles, he said. But a 2019 United Kingdom government study found that brake wear, tire wear, and road surface wear account for 72% of the PM 10 and 60% of the PM 2.5 pollution from road traffic, suggesting that a transition to electric vehicles won’t fix the problem. Better yet, is “the promotion of active modes like walking, cycling, etc., because like this, you can bring additional health gains due to the increase in physical activity,” he said.

Oncologists can help their patients reduce their exposure to air pollution, Dr. Schiller said. “If you have lung cancer, air pollution will hasten your demise. It makes you sicker. Oncologists should be telling their patients about this and advising them to move away from air pollution if possible, and also making sure they know to monitor the health of the air.”

On days when air pollution is high, patients may want to avoid exercising outdoors, or stay indoors altogether, Dr. Berg said. Air purifiers and N95 masks may also help.

And physicians can make a difference by speaking out in their communities, Dr. Schiller said. She is inviting oncologists to join a new group, Oncologists Understanding for Climate and Health. Through this group or on their own, oncologists can speak to their local legislatures or city councils in support of measures to reduce pollution, she said. “Doctors are trusted messengers.”

Dr. Berg disclosed affiliations with Grail, Mercy BioAnalytics and Lucid Diagnostics.

Identification of pulmonary nodules in older adults who smoke immediately brings concern for malignancy in the mind of clinicians. This is particularly the case in patients with significant smoking history. According to the National Cancer Institute in 2019, 12.9% of all new cancer cases were lung cancers.¹ Screening for lung cancer, especially in patients with increased risk from smoking, is imperative to early detection and treatment. However, 20% of patients will be overdiagnosed by lung cancer-screening techniques.² The rate of malignancy noted on a patient’s first screening computed tomography (CT) scan was between 3.7% and 5.5%.³

Rheumatoid arthritis (RA) is an autoimmune inflammatory condition that mainly affects the joints. Extraarticular manifestations can arise in various locations throughout the body, however. These manifestations are commonly observed in the skin, heart, and lungs.⁴ Prevalence of pulmonary rheumatoid nodules ranges from < 0.4% in radiologic studies to 32% in lung biopsies of patients with RA and nodules.⁵

Furthermore, there is a strong association between the risk of rheumatoid nodules in patients with positive serum rheumatoid factor (RF) and smoking history.⁶ Solitary pulmonary nodules in patients with RA can coexist with bronchogenic carcinoma, making their diagnosis more important.⁷

Case Presentation

A 54-year-old woman with a 30 pack-year smoking history and history of RA initially presented to the emergency department for cough and dyspnea for 5-day duration. Her initial diagnosis was bronchitis based on presenting symptom profile. A chest CT demonstrated 3 cavitary pulmonary nodules, 1 measuring 2.4 x 2.0 cm in the right middle lobe, and 2 additional nodules, measuring 1.8 x 1.4 and 1.5 x 1.4 in the left upper lobe (Figure). She had no improvement of symptoms after a 7-day course of doxycycline. The patient was taking methotrexate 15 mg weekly and golimumab 50 mg subcutaneously every 4 weeks as treatment for RA, prescribed by her rheumatologist.

Pulmonology was consulted and a positron emission tomography-CT (PET-CT) confirmed several cavitary pulmonary nodules involving both lungs with no suspicious fluorodeoxyglucose (FDG) uptake. The largest lesion was in the right middle lobe with FDG uptake of 1.9. Additional nodules were found in the left upper lobe, measuring 1.8 x 1.4 cm with FDG of 4.01, and in the left lung apex, measuring 1.5 x 1.4 cm with uptake of 3.53. CTguided percutaneous fine needle aspiration (PFNA) of the right middle lobe lung nodule demonstrated granuloma with central inflammatory debris. Grocott methenamine silver (GMS) stain was negative for fungal organism, acid-fast bacteria (AFB) stain was negative for acid-fast bacilli, and CD20 and CD3 immunostaining demonstrated mixed B- and T-cell populations. There was no evidence of atypia or malignancy. The biopsy demonstrated granuloma with central inflammatory debris on a background of densely fibrotic tissue and lympho-plasmatic inflammation. This finding confirmed the diagnosis of RA with pulmonary involvement.

Outpatient follow-up was established with a pulmonologist and rheumatologist. Methotrexate 15 mg weekly and golimumab subcutaneously 50 mg every 4 weeks were prescribed for the patient. The nodules are being monitored based on Fleischer guidelines with CT imaging 3 to 6 months following initial presentation. Further imaging will be considered at 18 to 24 months as well to further assess stability of the nodules and monitor for changes in size, shape, and necrosis. The patient also was encouraged to quit smoking. Her clinical course since the diagnosis has been stable.

Discussion

The differential diagnosis for new multiple pulmonary nodules on imaging studies is broad and includes infectious processes, such as tuberculosis, as well as other mycobacterial, fungal, and bacterial infections. Noninfectious causes of lung disease are an even broader category of consideration. Noninfectious pulmonary nodules differential includes sarcoidosis, granulomatous with polyangiitis, hypersensitivity pneumonitis, methotrexate drug reaction, pulmonary manifestations of systemic conditions, such as RA chronic granulomatous disease and malignancy.⁸ Bronchogenic carcinoma was suspected in this patient due to her smoking history. Squamous cell carcinoma was also considered as the lesion was cavitary. AFB and GMS stains were negative for fungi. Langerhans cell histiocytosis were considered but ruled out as these lesions contain larger numbers of eosinophils than described in the pathology report. Histoplasma and coccidiosis laboratory tests were obtained as the patient lived in a region endemic to both these fungi but were negative (Table). A diagnosis of rheumatoid nodule was made based on the clinical setting, typical radiographic, histopathology features, and negative cultures.

This case is unique due to the quality and location of the rheumatoid nodules within the lungs. Pulmonary manifestations of RA are usually subcutaneous or subpleural, solid, and peripherally located^.9 This patient’s nodules were necrobiotic and located within the lung parenchyma. There was significant cavitation. These factors are atypical features of pulmonary RA.

Pulmonary RA can have many associated symptoms and remains an important factor in patient mortality. Estimates demonstrate that 10 to 20% of RA-related deaths are secondary to pulmonary manifestations.¹⁰ There are a wide array of symptoms and presentations to be aware of clinically. These symptoms are often nondescript, widely sensitive to many disease processes, and nonspecific to pulmonary RA. These symptoms include dyspnea, wheezing, and nonproductive cough.¹⁰ Bronchiectasis is a common symptom as well as small airway obstruction.¹⁰ Consolidated necrobiotic lesions are present in up to 20% of pulmonary RA cases.¹⁰ Generally these lesions are asymptomatic but can also be associated with pneumothorax, hemoptysis, and airway obstruction.10 Awareness of these symptoms is important for diagnosis and monitoring clinical improvement in patients.

Further workup is necessary to differentiate malignancy-related pulmonary nodules and other causes; if the index of suspicion is high for malignancy as in our case, the workup should be more aggressive. Biopsy is mandatory in such cases to rule out infections and malignancy, as it is highly sensitive and specific. The main problem hindering management is when a clinician fails to include this in their differential diagnosis. This further elucidates the importance of awareness of this diagnosis. Suspicious lesions in a proper clinical setting should be followed up by imaging studies and confirmatory histopathological diagnosis. Typical follow-up is 3 months after initial presentation to assess stability and possibly 18 to 24 months as well based on Fleischer guidelines.

Various treatment modalities have been tried as per literature, including tocilizumab and rituximab. ^11,12 Our patient is currently being treated with golimumab based on outpatient rheumatologist recommendations.

Conclusions

This case demonstrates the importance of a careful workup to narrow a broad differential. Medical diagnosis of pulmonary nodules requires an in-depth workup, including clinical evaluation, laboratory and pulmonary functions tests, as well as various imaging studies.

Identification of pulmonary nodules in older adults who smoke immediately brings concern for malignancy in the mind of clinicians. This is particularly the case in patients with significant smoking history. According to the National Cancer Institute in 2019, 12.9% of all new cancer cases were lung cancers.¹ Screening for lung cancer, especially in patients with increased risk from smoking, is imperative to early detection and treatment. However, 20% of patients will be overdiagnosed by lung cancer-screening techniques.² The rate of malignancy noted on a patient’s first screening computed tomography (CT) scan was between 3.7% and 5.5%.³

Rheumatoid arthritis (RA) is an autoimmune inflammatory condition that mainly affects the joints. Extraarticular manifestations can arise in various locations throughout the body, however. These manifestations are commonly observed in the skin, heart, and lungs.⁴ Prevalence of pulmonary rheumatoid nodules ranges from < 0.4% in radiologic studies to 32% in lung biopsies of patients with RA and nodules.⁵

Furthermore, there is a strong association between the risk of rheumatoid nodules in patients with positive serum rheumatoid factor (RF) and smoking history.⁶ Solitary pulmonary nodules in patients with RA can coexist with bronchogenic carcinoma, making their diagnosis more important.⁷

Case Presentation

A 54-year-old woman with a 30 pack-year smoking history and history of RA initially presented to the emergency department for cough and dyspnea for 5-day duration. Her initial diagnosis was bronchitis based on presenting symptom profile. A chest CT demonstrated 3 cavitary pulmonary nodules, 1 measuring 2.4 x 2.0 cm in the right middle lobe, and 2 additional nodules, measuring 1.8 x 1.4 and 1.5 x 1.4 in the left upper lobe (Figure). She had no improvement of symptoms after a 7-day course of doxycycline. The patient was taking methotrexate 15 mg weekly and golimumab 50 mg subcutaneously every 4 weeks as treatment for RA, prescribed by her rheumatologist.

Pulmonology was consulted and a positron emission tomography-CT (PET-CT) confirmed several cavitary pulmonary nodules involving both lungs with no suspicious fluorodeoxyglucose (FDG) uptake. The largest lesion was in the right middle lobe with FDG uptake of 1.9. Additional nodules were found in the left upper lobe, measuring 1.8 x 1.4 cm with FDG of 4.01, and in the left lung apex, measuring 1.5 x 1.4 cm with uptake of 3.53. CTguided percutaneous fine needle aspiration (PFNA) of the right middle lobe lung nodule demonstrated granuloma with central inflammatory debris. Grocott methenamine silver (GMS) stain was negative for fungal organism, acid-fast bacteria (AFB) stain was negative for acid-fast bacilli, and CD20 and CD3 immunostaining demonstrated mixed B- and T-cell populations. There was no evidence of atypia or malignancy. The biopsy demonstrated granuloma with central inflammatory debris on a background of densely fibrotic tissue and lympho-plasmatic inflammation. This finding confirmed the diagnosis of RA with pulmonary involvement.

Outpatient follow-up was established with a pulmonologist and rheumatologist. Methotrexate 15 mg weekly and golimumab subcutaneously 50 mg every 4 weeks were prescribed for the patient. The nodules are being monitored based on Fleischer guidelines with CT imaging 3 to 6 months following initial presentation. Further imaging will be considered at 18 to 24 months as well to further assess stability of the nodules and monitor for changes in size, shape, and necrosis. The patient also was encouraged to quit smoking. Her clinical course since the diagnosis has been stable.

Discussion

The differential diagnosis for new multiple pulmonary nodules on imaging studies is broad and includes infectious processes, such as tuberculosis, as well as other mycobacterial, fungal, and bacterial infections. Noninfectious causes of lung disease are an even broader category of consideration. Noninfectious pulmonary nodules differential includes sarcoidosis, granulomatous with polyangiitis, hypersensitivity pneumonitis, methotrexate drug reaction, pulmonary manifestations of systemic conditions, such as RA chronic granulomatous disease and malignancy.⁸ Bronchogenic carcinoma was suspected in this patient due to her smoking history. Squamous cell carcinoma was also considered as the lesion was cavitary. AFB and GMS stains were negative for fungi. Langerhans cell histiocytosis were considered but ruled out as these lesions contain larger numbers of eosinophils than described in the pathology report. Histoplasma and coccidiosis laboratory tests were obtained as the patient lived in a region endemic to both these fungi but were negative (Table). A diagnosis of rheumatoid nodule was made based on the clinical setting, typical radiographic, histopathology features, and negative cultures.

This case is unique due to the quality and location of the rheumatoid nodules within the lungs. Pulmonary manifestations of RA are usually subcutaneous or subpleural, solid, and peripherally located^.9 This patient’s nodules were necrobiotic and located within the lung parenchyma. There was significant cavitation. These factors are atypical features of pulmonary RA.

Pulmonary RA can have many associated symptoms and remains an important factor in patient mortality. Estimates demonstrate that 10 to 20% of RA-related deaths are secondary to pulmonary manifestations.¹⁰ There are a wide array of symptoms and presentations to be aware of clinically. These symptoms are often nondescript, widely sensitive to many disease processes, and nonspecific to pulmonary RA. These symptoms include dyspnea, wheezing, and nonproductive cough.¹⁰ Bronchiectasis is a common symptom as well as small airway obstruction.¹⁰ Consolidated necrobiotic lesions are present in up to 20% of pulmonary RA cases.¹⁰ Generally these lesions are asymptomatic but can also be associated with pneumothorax, hemoptysis, and airway obstruction.10 Awareness of these symptoms is important for diagnosis and monitoring clinical improvement in patients.

Further workup is necessary to differentiate malignancy-related pulmonary nodules and other causes; if the index of suspicion is high for malignancy as in our case, the workup should be more aggressive. Biopsy is mandatory in such cases to rule out infections and malignancy, as it is highly sensitive and specific. The main problem hindering management is when a clinician fails to include this in their differential diagnosis. This further elucidates the importance of awareness of this diagnosis. Suspicious lesions in a proper clinical setting should be followed up by imaging studies and confirmatory histopathological diagnosis. Typical follow-up is 3 months after initial presentation to assess stability and possibly 18 to 24 months as well based on Fleischer guidelines.

Various treatment modalities have been tried as per literature, including tocilizumab and rituximab. ^11,12 Our patient is currently being treated with golimumab based on outpatient rheumatologist recommendations.

Conclusions

This case demonstrates the importance of a careful workup to narrow a broad differential. Medical diagnosis of pulmonary nodules requires an in-depth workup, including clinical evaluation, laboratory and pulmonary functions tests, as well as various imaging studies.

Identification of pulmonary nodules in older adults who smoke immediately brings concern for malignancy in the mind of clinicians. This is particularly the case in patients with significant smoking history. According to the National Cancer Institute in 2019, 12.9% of all new cancer cases were lung cancers.¹ Screening for lung cancer, especially in patients with increased risk from smoking, is imperative to early detection and treatment. However, 20% of patients will be overdiagnosed by lung cancer-screening techniques.² The rate of malignancy noted on a patient’s first screening computed tomography (CT) scan was between 3.7% and 5.5%.³

Rheumatoid arthritis (RA) is an autoimmune inflammatory condition that mainly affects the joints. Extraarticular manifestations can arise in various locations throughout the body, however. These manifestations are commonly observed in the skin, heart, and lungs.⁴ Prevalence of pulmonary rheumatoid nodules ranges from < 0.4% in radiologic studies to 32% in lung biopsies of patients with RA and nodules.⁵

Furthermore, there is a strong association between the risk of rheumatoid nodules in patients with positive serum rheumatoid factor (RF) and smoking history.⁶ Solitary pulmonary nodules in patients with RA can coexist with bronchogenic carcinoma, making their diagnosis more important.⁷

Case Presentation

A 54-year-old woman with a 30 pack-year smoking history and history of RA initially presented to the emergency department for cough and dyspnea for 5-day duration. Her initial diagnosis was bronchitis based on presenting symptom profile. A chest CT demonstrated 3 cavitary pulmonary nodules, 1 measuring 2.4 x 2.0 cm in the right middle lobe, and 2 additional nodules, measuring 1.8 x 1.4 and 1.5 x 1.4 in the left upper lobe (Figure). She had no improvement of symptoms after a 7-day course of doxycycline. The patient was taking methotrexate 15 mg weekly and golimumab 50 mg subcutaneously every 4 weeks as treatment for RA, prescribed by her rheumatologist.

Pulmonology was consulted and a positron emission tomography-CT (PET-CT) confirmed several cavitary pulmonary nodules involving both lungs with no suspicious fluorodeoxyglucose (FDG) uptake. The largest lesion was in the right middle lobe with FDG uptake of 1.9. Additional nodules were found in the left upper lobe, measuring 1.8 x 1.4 cm with FDG of 4.01, and in the left lung apex, measuring 1.5 x 1.4 cm with uptake of 3.53. CTguided percutaneous fine needle aspiration (PFNA) of the right middle lobe lung nodule demonstrated granuloma with central inflammatory debris. Grocott methenamine silver (GMS) stain was negative for fungal organism, acid-fast bacteria (AFB) stain was negative for acid-fast bacilli, and CD20 and CD3 immunostaining demonstrated mixed B- and T-cell populations. There was no evidence of atypia or malignancy. The biopsy demonstrated granuloma with central inflammatory debris on a background of densely fibrotic tissue and lympho-plasmatic inflammation. This finding confirmed the diagnosis of RA with pulmonary involvement.

Outpatient follow-up was established with a pulmonologist and rheumatologist. Methotrexate 15 mg weekly and golimumab subcutaneously 50 mg every 4 weeks were prescribed for the patient. The nodules are being monitored based on Fleischer guidelines with CT imaging 3 to 6 months following initial presentation. Further imaging will be considered at 18 to 24 months as well to further assess stability of the nodules and monitor for changes in size, shape, and necrosis. The patient also was encouraged to quit smoking. Her clinical course since the diagnosis has been stable.

Discussion

The differential diagnosis for new multiple pulmonary nodules on imaging studies is broad and includes infectious processes, such as tuberculosis, as well as other mycobacterial, fungal, and bacterial infections. Noninfectious causes of lung disease are an even broader category of consideration. Noninfectious pulmonary nodules differential includes sarcoidosis, granulomatous with polyangiitis, hypersensitivity pneumonitis, methotrexate drug reaction, pulmonary manifestations of systemic conditions, such as RA chronic granulomatous disease and malignancy.⁸ Bronchogenic carcinoma was suspected in this patient due to her smoking history. Squamous cell carcinoma was also considered as the lesion was cavitary. AFB and GMS stains were negative for fungi. Langerhans cell histiocytosis were considered but ruled out as these lesions contain larger numbers of eosinophils than described in the pathology report. Histoplasma and coccidiosis laboratory tests were obtained as the patient lived in a region endemic to both these fungi but were negative (Table). A diagnosis of rheumatoid nodule was made based on the clinical setting, typical radiographic, histopathology features, and negative cultures.

This case is unique due to the quality and location of the rheumatoid nodules within the lungs. Pulmonary manifestations of RA are usually subcutaneous or subpleural, solid, and peripherally located^.9 This patient’s nodules were necrobiotic and located within the lung parenchyma. There was significant cavitation. These factors are atypical features of pulmonary RA.

Pulmonary RA can have many associated symptoms and remains an important factor in patient mortality. Estimates demonstrate that 10 to 20% of RA-related deaths are secondary to pulmonary manifestations.¹⁰ There are a wide array of symptoms and presentations to be aware of clinically. These symptoms are often nondescript, widely sensitive to many disease processes, and nonspecific to pulmonary RA. These symptoms include dyspnea, wheezing, and nonproductive cough.¹⁰ Bronchiectasis is a common symptom as well as small airway obstruction.¹⁰ Consolidated necrobiotic lesions are present in up to 20% of pulmonary RA cases.¹⁰ Generally these lesions are asymptomatic but can also be associated with pneumothorax, hemoptysis, and airway obstruction.10 Awareness of these symptoms is important for diagnosis and monitoring clinical improvement in patients.

Further workup is necessary to differentiate malignancy-related pulmonary nodules and other causes; if the index of suspicion is high for malignancy as in our case, the workup should be more aggressive. Biopsy is mandatory in such cases to rule out infections and malignancy, as it is highly sensitive and specific. The main problem hindering management is when a clinician fails to include this in their differential diagnosis. This further elucidates the importance of awareness of this diagnosis. Suspicious lesions in a proper clinical setting should be followed up by imaging studies and confirmatory histopathological diagnosis. Typical follow-up is 3 months after initial presentation to assess stability and possibly 18 to 24 months as well based on Fleischer guidelines.

Various treatment modalities have been tried as per literature, including tocilizumab and rituximab. ^11,12 Our patient is currently being treated with golimumab based on outpatient rheumatologist recommendations.

Conclusions

This case demonstrates the importance of a careful workup to narrow a broad differential. Medical diagnosis of pulmonary nodules requires an in-depth workup, including clinical evaluation, laboratory and pulmonary functions tests, as well as various imaging studies.

Although mesothelioma continues to be a very difficult disease to treat and one with a poor prognosis, new and emerging therapeutic developments hold the promise of extending survival for appropriately selected patients.

Following years of little to no movement, encouraging advances in treatment have been seen on the immunotherapy front. Immune checkpoint inhibitors have demonstrated acceptable safety and promising efficacy in the treatment of unresectable malignant pleural mesothelioma (MPM), including an overall survival advantage over standard-of-care first-line chemotherapy. Beyond systemic therapy, the development of new radiation techniques to complement current, more conservative surgical approaches is likewise encouraging, though further randomized clinical trial data is awaited to determine the potential impact on survival.

Longer survival would be good news for the estimated 3,000 individuals diagnosed with MPM each year in the United States. Overall, the outlook for patients with this rare cancer remains unfavorable, with a 5-year survival rate of about 11%, according to data from the U.S. Surveillance, Epidemiology and End Results (SEER) Program.

One factor underlying that grim survival statistic is a relative lack of investment in the development of drugs specific to rare cancers, as compared to more common malignancies, said Anne S. Tsao, MD, professor and director of the mesothelioma program at the University of Texas MD Anderson Cancer Center in Houston.

Du Cane Medical Imaging Ltd/Science Source

Checkpoint inhibitors

Multiple checkpoint inhibitors have received Food and Drug Administration approval for the treatment of non–small cell lung cancer (NSCLC) over the past few years. Because many mesothelioma doctors also treat NSCLC, bringing those agents into the mesothelioma sphere was not a very difficult jump, Dr. Tsao said.

Checkpoint inhibitors got a foothold in mesothelioma, much like in NSCLC, by demonstrating clear benefit in the salvage setting, according to Dr. Tsao.

Pembrolizumab, nivolumab, and avelumab were evaluated in phase 1b/2 clinical trials and real-world cohorts that demonstrated response rates of around 20%, median progression-free survival of 4 months, and median overall survival (OS) around 12 months in patients with previously treated MPM.

Although results of those early-stage studies had to be interpreted with caution, they nonetheless suggested a slight edge for these checkpoint inhibitors over historical data, according to the authors of a recent article in Cancer Treatment Reviews.¹ On the basis of phase 1 and 2 data, current clinical practice guidelines from the National Comprehensive Cancer Network² list pembrolizumab and the combination of nivolumab and ipilimumab as options for MPM patients who have received previous therapy. Phase 3 trials have also been launched, including PROMISE-meso, which is comparing pembrolizumab to single-agent chemotherapy in advanced, pretreated MPM³, and CONFIRM, which pits nivolumab against placebo in relapsed MPM.⁴

On the front lines

Encouraging results in previously treated MPM led to the evaluation of checkpoint inhibitors as first-line therapy. Notably, the FDA approved nivolumab given with ipilimumab for the treatment of patients with unresectable MPM in October 2020, making that combination the first immunotherapy regimen to receive an indication in this disease.

The FDA approval was based on prespecified interim analysis of CheckMate 743, a phase 3 study that included 605 patients randomly allocated to nivolumab plus ipilimumab or to placebo.

At the interim analysis, median OS was 18.1 months for nivolumab plus ipilimumab, versus just 14.1 months for placebo (hazard ratio, 0.74; 96.6% confidence interval, 0.60-0.91; P = 0.0020), according to results of the study published in the Lancet.⁵ The 2-year OS rate was 41% for the immunotherapy combination and 27% for placebo. Grade 3-4 treatment-related adverse events were seen in 30% of the immunotherapy-treated patients and 32% of the chemotherapy-treated patients.

The magnitude of nivolumab-ipilimumab benefit appeared to be largest among patients with non-epithelioid MPM subtypes (sarcomatoid and biphasic), owing to the inferior impact of chemotherapy in these patients, with a median OS of just 8.8 months, according to investigators.

That’s not to say that immunotherapy didn’t work for patients with epithelioid histology. The benefit of nivolumab-ipilimumab was consistent for non-epithelioid and epithelioid patient subsets, with median OS of 18.1 and 18.7 months, respectively, results of subgroup analysis showed.

According to Dr. Tsao, those results reflect the extremely poor prognosis and pressing need for effective therapy early in the course of treatment for patients with non-epithelioid histology.

“You have to get the most effective therapy into these patients as quickly as you can,” she explained. “If you can get the more effective treatment and early, then you’ll see a longer-term benefit for them.”

Role of the PD-L1 biomarker

Despite this progress, one key hurdle has been determining the role of the PD-L1 biomarker in mesothelioma. In NSCLC, PD-L1 is often used to determine which patients will benefit from immune checkpoint inhibitors. In mesothelioma, the correlations have been more elusive.

Among patients in the CheckMate 743 study treated with nivolumab plus ipilimumab, OS was not significantly different for those with PD-L1 expression levels of less than 1% and those with 1% or greater, investigators said. Moreover, PD-L1 expression wasn’t a stratification factor in the study.

“When looking at all of the studies, it appears that the checkpoint inhibitors can truly benefit a certain percentage of mesothelioma patients, but we can’t pick them out just yet,” Dr. Tsao said.

“So our recommendation is to offer [checkpoint inhibitor therapy] at some point in their treatment, whether it’s first, second, or third line,” she continued. “They can get some benefit, and even in those if you don’t get a great response, you can still get disease stabilization, which in and of itself can be highly beneficial.”

Future directions

Immune checkpoint inhibitor–based combination regimens and cellular therapy represent promising directions forward in MPM research. There are several notable phase 3 trials of checkpoint inhibitors plus chemotherapy and targeted therapy going forward, plus intriguing data emerging on the potential role of chimeric antigen receptor (CAR) T-cell therapy in this setting.

One phase 3 trial to watch is IND277, which is comparing pembrolizumab plus cisplatin/pemetrexed chemotherapy to cisplatin/pemetrexed alone; that trial has enrolled 520 participants and has an estimated primary completion date in July 2022, according to the ClinicalTrials.gov website. Another is BEAT-Meso, a comparison of atezolizumab plus bevacizumab and chemotherapy against bevacizumab and chemotherapy, which has an estimated enrollment of 400 participants and primary completion date of January 2024. A third trial of interest is DREAM3R, which compares durvalumab plus chemotherapy followed by durvalumab maintenance to standard chemotherapy followed by observation. That study should enroll 480 participants and has an estimated primary completion date of April 2025.

CAR T-cell therapy, while best known for its emerging role in the treatment of hematologic malignancies, may also have a place in mesothelioma therapy one day. In a recently published report, investigators described a first-in-human phase I study of a mesothelin-targeted CAR T-cell therapy given in combination with pembrolizumab. Among 18 MPM patients who received pembrolizumab safely, median OS from time of CAR T-cell infusion was 23.9 months and 1-year OS was 83%, according to investigators.⁶An OS of nearly 24 months is “very encouraging” and compares favorably with historical results with systemic therapy in this difficult-to-treat disease, said Jacques P. Fontaine, MD, a thoracic surgeon and section head of mesothelioma research and treatment center at Moffitt Cancer Center in Tampa, Fla.

“It’s huge, but you have to take into account that this [OS] is still less than 2 years,” Dr. Fontaine said in an interview. “There’s still a lot of work to be done.”

Radiotherapy making an IMPRINT

Meanwhile, new developments in the multimodality treatment of resectable MPM are progressing and have the potential to extend survival among patients who undergo lung-sparing surgery.

Less aggressive intervention is increasingly the preferred approach to surgery in this patient population. That shift is supported by studies showing that lung-sparing pleurectomy-decortication (P/D) resulted in less morbidity and potentially better survival outcomes than extrapleural pneumonectomy (EPP), according to Andreas Rimner, MD, associate attending physician and director of thoracic radiation oncology research at Memorial Sloan Kettering Cancer Center in New York.

However, it is more challenging to deliver radiotherapy safely in patients who have undergone P/D as compared with patients who have undergone EPP, according to Dr. Rimner.

“When there’s no lung in place [as in EPP], it’s pretty simple – you just treat the entire empty chest to kill any microscopic cells that may still be left behind,” he said in an interview. “But now we have a situation where both lungs are still in place, and they are very radiation sensitive, so that’s not an easy feat.”

Driven by the limitations of conventional radiation, Dr. Rimner and colleagues developed a novel technique known as hemithoracic intensity-modulated pleural radiation therapy (IMPRINT) that allows more precise application of radiotherapy.

In a phase 2 study published in 2016, IMPRINT was found to be safe, with an acceptable rate of radiation pneumonitis (30% grade 2 or 3), according to investigators.⁷

Subsequent studies have demonstrated encouraging clinical outcomes, including a 20.2-month median OS for IMPRINT versus 12.3 months for conventional adjuvant radiotherapy in a retrospective study of 209 patients who underwent P/D between 1975 and 2015.⁸ Those findings led to the development of a phase 3 trial known as NRG-LU006 that is evaluating P/D plus chemotherapy with or without adjuvant IMPRINT in an estimated 150 patients. The study has a primary endpoint of OS, and an estimated primary completion date in July 2025, according to ClinicalTrials.gov.

Dr. Rimner said he’s optimistic about the prospects of this study, particularly with recently published results of a phase 3 study in which Italian investigators demonstrated an OS benefit of IMPRINT over palliative radiation in patients with nonmetastatic MPM.⁹

“That’s more data and rationale that shows there is good reason to believe that we are adding something here with this radiation technique,” said Dr. Rimner.

Dr. Fontaine, the thoracic surgeon and mesothelioma research head at Moffitt Cancer Center, said he’s hoping to see a substantial impact of IMPRINT on disease-free survival (DFS) once results of NRG-LU006 are available.

“I think DFS plays a role that we’ve underestimated over the last few years for sure,” he said.

For a patient with MPM, a short DFS can be anxiety provoking and may have negative impacts on quality of life, even despite a long OS, he explained.

“In terms of your outlook on life, how many times you have to go see a doctor, and how you enjoy life, there’s a big difference between the two,” he said.

Dr. Tsao provided disclosures related to Ariad, AstraZeneca, BMS, Boehringer Ingelheim, Eli Lilly, EMD Serono, Epizyme, Genentech, Huron, Merck, Millennium, Novartis, Polaris, Roche, Seattle Genetics, SELLAS Life Sciences Group, and Takeda. Dr. Fontaine reported no relevant disclosures. Dr. Rimner reported disclosures related to Bristol-Myers Squibb, GE Healthcare, Varian Medical Systems, and Boehringer Ingelheim.

References

1. Parikh K et al. Cancer Treat Rev. 2021 Sept 1;99:102250.

2. National Comprehensive Cancer Network (NCCN) Guidelines. Malignant Pleural Mesothelioma. Version 2.2021, published 2021 Feb 16. Accessed 2021 Aug 30. https://www.nccn.org/professionals/physician_gls/pdf/mpm.pdf

3. Popat S et al. Ann Oncol. 2020;31(12):1734-45.

4. Fennell D et al. Journal of Thoracic Oncology. 2021 Mar 1;16(3):S62.

5. Baas P et al. [published correction appears in Lancet. 2021 Feb 20;397(10275):670]. Lancet. 2021 Jan 30;397(10272):375-86.

6. Adusumilli PS et al. Cancer Discov. 2021 Jul 15;candisc.0407.2021.

7. Rimner A et al. J Clin Oncol. 2016;34(23):2761-8.

8. Shaikh F et al. J Thorac Oncol. 2017;12(6):993-1000.

9. Trovo M et al. Int J Radiat Oncol Biol Phys. 2021;109(5):1368-76.

Although mesothelioma continues to be a very difficult disease to treat and one with a poor prognosis, new and emerging therapeutic developments hold the promise of extending survival for appropriately selected patients.

Following years of little to no movement, encouraging advances in treatment have been seen on the immunotherapy front. Immune checkpoint inhibitors have demonstrated acceptable safety and promising efficacy in the treatment of unresectable malignant pleural mesothelioma (MPM), including an overall survival advantage over standard-of-care first-line chemotherapy. Beyond systemic therapy, the development of new radiation techniques to complement current, more conservative surgical approaches is likewise encouraging, though further randomized clinical trial data is awaited to determine the potential impact on survival.

Longer survival would be good news for the estimated 3,000 individuals diagnosed with MPM each year in the United States. Overall, the outlook for patients with this rare cancer remains unfavorable, with a 5-year survival rate of about 11%, according to data from the U.S. Surveillance, Epidemiology and End Results (SEER) Program.

One factor underlying that grim survival statistic is a relative lack of investment in the development of drugs specific to rare cancers, as compared to more common malignancies, said Anne S. Tsao, MD, professor and director of the mesothelioma program at the University of Texas MD Anderson Cancer Center in Houston.

Du Cane Medical Imaging Ltd/Science Source

Checkpoint inhibitors

Multiple checkpoint inhibitors have received Food and Drug Administration approval for the treatment of non–small cell lung cancer (NSCLC) over the past few years. Because many mesothelioma doctors also treat NSCLC, bringing those agents into the mesothelioma sphere was not a very difficult jump, Dr. Tsao said.

Checkpoint inhibitors got a foothold in mesothelioma, much like in NSCLC, by demonstrating clear benefit in the salvage setting, according to Dr. Tsao.

Pembrolizumab, nivolumab, and avelumab were evaluated in phase 1b/2 clinical trials and real-world cohorts that demonstrated response rates of around 20%, median progression-free survival of 4 months, and median overall survival (OS) around 12 months in patients with previously treated MPM.

Although results of those early-stage studies had to be interpreted with caution, they nonetheless suggested a slight edge for these checkpoint inhibitors over historical data, according to the authors of a recent article in Cancer Treatment Reviews.¹ On the basis of phase 1 and 2 data, current clinical practice guidelines from the National Comprehensive Cancer Network² list pembrolizumab and the combination of nivolumab and ipilimumab as options for MPM patients who have received previous therapy. Phase 3 trials have also been launched, including PROMISE-meso, which is comparing pembrolizumab to single-agent chemotherapy in advanced, pretreated MPM³, and CONFIRM, which pits nivolumab against placebo in relapsed MPM.⁴

On the front lines

Encouraging results in previously treated MPM led to the evaluation of checkpoint inhibitors as first-line therapy. Notably, the FDA approved nivolumab given with ipilimumab for the treatment of patients with unresectable MPM in October 2020, making that combination the first immunotherapy regimen to receive an indication in this disease.

The FDA approval was based on prespecified interim analysis of CheckMate 743, a phase 3 study that included 605 patients randomly allocated to nivolumab plus ipilimumab or to placebo.

At the interim analysis, median OS was 18.1 months for nivolumab plus ipilimumab, versus just 14.1 months for placebo (hazard ratio, 0.74; 96.6% confidence interval, 0.60-0.91; P = 0.0020), according to results of the study published in the Lancet.⁵ The 2-year OS rate was 41% for the immunotherapy combination and 27% for placebo. Grade 3-4 treatment-related adverse events were seen in 30% of the immunotherapy-treated patients and 32% of the chemotherapy-treated patients.

The magnitude of nivolumab-ipilimumab benefit appeared to be largest among patients with non-epithelioid MPM subtypes (sarcomatoid and biphasic), owing to the inferior impact of chemotherapy in these patients, with a median OS of just 8.8 months, according to investigators.

That’s not to say that immunotherapy didn’t work for patients with epithelioid histology. The benefit of nivolumab-ipilimumab was consistent for non-epithelioid and epithelioid patient subsets, with median OS of 18.1 and 18.7 months, respectively, results of subgroup analysis showed.

According to Dr. Tsao, those results reflect the extremely poor prognosis and pressing need for effective therapy early in the course of treatment for patients with non-epithelioid histology.

“You have to get the most effective therapy into these patients as quickly as you can,” she explained. “If you can get the more effective treatment and early, then you’ll see a longer-term benefit for them.”

Role of the PD-L1 biomarker

Despite this progress, one key hurdle has been determining the role of the PD-L1 biomarker in mesothelioma. In NSCLC, PD-L1 is often used to determine which patients will benefit from immune checkpoint inhibitors. In mesothelioma, the correlations have been more elusive.

Among patients in the CheckMate 743 study treated with nivolumab plus ipilimumab, OS was not significantly different for those with PD-L1 expression levels of less than 1% and those with 1% or greater, investigators said. Moreover, PD-L1 expression wasn’t a stratification factor in the study.

“When looking at all of the studies, it appears that the checkpoint inhibitors can truly benefit a certain percentage of mesothelioma patients, but we can’t pick them out just yet,” Dr. Tsao said.

“So our recommendation is to offer [checkpoint inhibitor therapy] at some point in their treatment, whether it’s first, second, or third line,” she continued. “They can get some benefit, and even in those if you don’t get a great response, you can still get disease stabilization, which in and of itself can be highly beneficial.”

Future directions

Immune checkpoint inhibitor–based combination regimens and cellular therapy represent promising directions forward in MPM research. There are several notable phase 3 trials of checkpoint inhibitors plus chemotherapy and targeted therapy going forward, plus intriguing data emerging on the potential role of chimeric antigen receptor (CAR) T-cell therapy in this setting.

One phase 3 trial to watch is IND277, which is comparing pembrolizumab plus cisplatin/pemetrexed chemotherapy to cisplatin/pemetrexed alone; that trial has enrolled 520 participants and has an estimated primary completion date in July 2022, according to the ClinicalTrials.gov website. Another is BEAT-Meso, a comparison of atezolizumab plus bevacizumab and chemotherapy against bevacizumab and chemotherapy, which has an estimated enrollment of 400 participants and primary completion date of January 2024. A third trial of interest is DREAM3R, which compares durvalumab plus chemotherapy followed by durvalumab maintenance to standard chemotherapy followed by observation. That study should enroll 480 participants and has an estimated primary completion date of April 2025.

CAR T-cell therapy, while best known for its emerging role in the treatment of hematologic malignancies, may also have a place in mesothelioma therapy one day. In a recently published report, investigators described a first-in-human phase I study of a mesothelin-targeted CAR T-cell therapy given in combination with pembrolizumab. Among 18 MPM patients who received pembrolizumab safely, median OS from time of CAR T-cell infusion was 23.9 months and 1-year OS was 83%, according to investigators.⁶An OS of nearly 24 months is “very encouraging” and compares favorably with historical results with systemic therapy in this difficult-to-treat disease, said Jacques P. Fontaine, MD, a thoracic surgeon and section head of mesothelioma research and treatment center at Moffitt Cancer Center in Tampa, Fla.

“It’s huge, but you have to take into account that this [OS] is still less than 2 years,” Dr. Fontaine said in an interview. “There’s still a lot of work to be done.”

Radiotherapy making an IMPRINT

Meanwhile, new developments in the multimodality treatment of resectable MPM are progressing and have the potential to extend survival among patients who undergo lung-sparing surgery.

Less aggressive intervention is increasingly the preferred approach to surgery in this patient population. That shift is supported by studies showing that lung-sparing pleurectomy-decortication (P/D) resulted in less morbidity and potentially better survival outcomes than extrapleural pneumonectomy (EPP), according to Andreas Rimner, MD, associate attending physician and director of thoracic radiation oncology research at Memorial Sloan Kettering Cancer Center in New York.

However, it is more challenging to deliver radiotherapy safely in patients who have undergone P/D as compared with patients who have undergone EPP, according to Dr. Rimner.

“When there’s no lung in place [as in EPP], it’s pretty simple – you just treat the entire empty chest to kill any microscopic cells that may still be left behind,” he said in an interview. “But now we have a situation where both lungs are still in place, and they are very radiation sensitive, so that’s not an easy feat.”

Driven by the limitations of conventional radiation, Dr. Rimner and colleagues developed a novel technique known as hemithoracic intensity-modulated pleural radiation therapy (IMPRINT) that allows more precise application of radiotherapy.

In a phase 2 study published in 2016, IMPRINT was found to be safe, with an acceptable rate of radiation pneumonitis (30% grade 2 or 3), according to investigators.⁷

Subsequent studies have demonstrated encouraging clinical outcomes, including a 20.2-month median OS for IMPRINT versus 12.3 months for conventional adjuvant radiotherapy in a retrospective study of 209 patients who underwent P/D between 1975 and 2015.⁸ Those findings led to the development of a phase 3 trial known as NRG-LU006 that is evaluating P/D plus chemotherapy with or without adjuvant IMPRINT in an estimated 150 patients. The study has a primary endpoint of OS, and an estimated primary completion date in July 2025, according to ClinicalTrials.gov.

Dr. Rimner said he’s optimistic about the prospects of this study, particularly with recently published results of a phase 3 study in which Italian investigators demonstrated an OS benefit of IMPRINT over palliative radiation in patients with nonmetastatic MPM.⁹

“That’s more data and rationale that shows there is good reason to believe that we are adding something here with this radiation technique,” said Dr. Rimner.

Dr. Fontaine, the thoracic surgeon and mesothelioma research head at Moffitt Cancer Center, said he’s hoping to see a substantial impact of IMPRINT on disease-free survival (DFS) once results of NRG-LU006 are available.

“I think DFS plays a role that we’ve underestimated over the last few years for sure,” he said.

For a patient with MPM, a short DFS can be anxiety provoking and may have negative impacts on quality of life, even despite a long OS, he explained.

“In terms of your outlook on life, how many times you have to go see a doctor, and how you enjoy life, there’s a big difference between the two,” he said.

Dr. Tsao provided disclosures related to Ariad, AstraZeneca, BMS, Boehringer Ingelheim, Eli Lilly, EMD Serono, Epizyme, Genentech, Huron, Merck, Millennium, Novartis, Polaris, Roche, Seattle Genetics, SELLAS Life Sciences Group, and Takeda. Dr. Fontaine reported no relevant disclosures. Dr. Rimner reported disclosures related to Bristol-Myers Squibb, GE Healthcare, Varian Medical Systems, and Boehringer Ingelheim.

References

1. Parikh K et al. Cancer Treat Rev. 2021 Sept 1;99:102250.

2. National Comprehensive Cancer Network (NCCN) Guidelines. Malignant Pleural Mesothelioma. Version 2.2021, published 2021 Feb 16. Accessed 2021 Aug 30. https://www.nccn.org/professionals/physician_gls/pdf/mpm.pdf

3. Popat S et al. Ann Oncol. 2020;31(12):1734-45.

4. Fennell D et al. Journal of Thoracic Oncology. 2021 Mar 1;16(3):S62.

5. Baas P et al. [published correction appears in Lancet. 2021 Feb 20;397(10275):670]. Lancet. 2021 Jan 30;397(10272):375-86.

6. Adusumilli PS et al. Cancer Discov. 2021 Jul 15;candisc.0407.2021.

7. Rimner A et al. J Clin Oncol. 2016;34(23):2761-8.

8. Shaikh F et al. J Thorac Oncol. 2017;12(6):993-1000.

9. Trovo M et al. Int J Radiat Oncol Biol Phys. 2021;109(5):1368-76.

Although mesothelioma continues to be a very difficult disease to treat and one with a poor prognosis, new and emerging therapeutic developments hold the promise of extending survival for appropriately selected patients.

Following years of little to no movement, encouraging advances in treatment have been seen on the immunotherapy front. Immune checkpoint inhibitors have demonstrated acceptable safety and promising efficacy in the treatment of unresectable malignant pleural mesothelioma (MPM), including an overall survival advantage over standard-of-care first-line chemotherapy. Beyond systemic therapy, the development of new radiation techniques to complement current, more conservative surgical approaches is likewise encouraging, though further randomized clinical trial data is awaited to determine the potential impact on survival.

Longer survival would be good news for the estimated 3,000 individuals diagnosed with MPM each year in the United States. Overall, the outlook for patients with this rare cancer remains unfavorable, with a 5-year survival rate of about 11%, according to data from the U.S. Surveillance, Epidemiology and End Results (SEER) Program.

One factor underlying that grim survival statistic is a relative lack of investment in the development of drugs specific to rare cancers, as compared to more common malignancies, said Anne S. Tsao, MD, professor and director of the mesothelioma program at the University of Texas MD Anderson Cancer Center in Houston.

Du Cane Medical Imaging Ltd/Science Source

Checkpoint inhibitors

Multiple checkpoint inhibitors have received Food and Drug Administration approval for the treatment of non–small cell lung cancer (NSCLC) over the past few years. Because many mesothelioma doctors also treat NSCLC, bringing those agents into the mesothelioma sphere was not a very difficult jump, Dr. Tsao said.

Checkpoint inhibitors got a foothold in mesothelioma, much like in NSCLC, by demonstrating clear benefit in the salvage setting, according to Dr. Tsao.

Pembrolizumab, nivolumab, and avelumab were evaluated in phase 1b/2 clinical trials and real-world cohorts that demonstrated response rates of around 20%, median progression-free survival of 4 months, and median overall survival (OS) around 12 months in patients with previously treated MPM.

Although results of those early-stage studies had to be interpreted with caution, they nonetheless suggested a slight edge for these checkpoint inhibitors over historical data, according to the authors of a recent article in Cancer Treatment Reviews.¹ On the basis of phase 1 and 2 data, current clinical practice guidelines from the National Comprehensive Cancer Network² list pembrolizumab and the combination of nivolumab and ipilimumab as options for MPM patients who have received previous therapy. Phase 3 trials have also been launched, including PROMISE-meso, which is comparing pembrolizumab to single-agent chemotherapy in advanced, pretreated MPM³, and CONFIRM, which pits nivolumab against placebo in relapsed MPM.⁴

On the front lines

Encouraging results in previously treated MPM led to the evaluation of checkpoint inhibitors as first-line therapy. Notably, the FDA approved nivolumab given with ipilimumab for the treatment of patients with unresectable MPM in October 2020, making that combination the first immunotherapy regimen to receive an indication in this disease.

The FDA approval was based on prespecified interim analysis of CheckMate 743, a phase 3 study that included 605 patients randomly allocated to nivolumab plus ipilimumab or to placebo.

At the interim analysis, median OS was 18.1 months for nivolumab plus ipilimumab, versus just 14.1 months for placebo (hazard ratio, 0.74; 96.6% confidence interval, 0.60-0.91; P = 0.0020), according to results of the study published in the Lancet.⁵ The 2-year OS rate was 41% for the immunotherapy combination and 27% for placebo. Grade 3-4 treatment-related adverse events were seen in 30% of the immunotherapy-treated patients and 32% of the chemotherapy-treated patients.

The magnitude of nivolumab-ipilimumab benefit appeared to be largest among patients with non-epithelioid MPM subtypes (sarcomatoid and biphasic), owing to the inferior impact of chemotherapy in these patients, with a median OS of just 8.8 months, according to investigators.

That’s not to say that immunotherapy didn’t work for patients with epithelioid histology. The benefit of nivolumab-ipilimumab was consistent for non-epithelioid and epithelioid patient subsets, with median OS of 18.1 and 18.7 months, respectively, results of subgroup analysis showed.

According to Dr. Tsao, those results reflect the extremely poor prognosis and pressing need for effective therapy early in the course of treatment for patients with non-epithelioid histology.

“You have to get the most effective therapy into these patients as quickly as you can,” she explained. “If you can get the more effective treatment and early, then you’ll see a longer-term benefit for them.”

Role of the PD-L1 biomarker

Despite this progress, one key hurdle has been determining the role of the PD-L1 biomarker in mesothelioma. In NSCLC, PD-L1 is often used to determine which patients will benefit from immune checkpoint inhibitors. In mesothelioma, the correlations have been more elusive.

Among patients in the CheckMate 743 study treated with nivolumab plus ipilimumab, OS was not significantly different for those with PD-L1 expression levels of less than 1% and those with 1% or greater, investigators said. Moreover, PD-L1 expression wasn’t a stratification factor in the study.

“When looking at all of the studies, it appears that the checkpoint inhibitors can truly benefit a certain percentage of mesothelioma patients, but we can’t pick them out just yet,” Dr. Tsao said.

“So our recommendation is to offer [checkpoint inhibitor therapy] at some point in their treatment, whether it’s first, second, or third line,” she continued. “They can get some benefit, and even in those if you don’t get a great response, you can still get disease stabilization, which in and of itself can be highly beneficial.”

Future directions

Immune checkpoint inhibitor–based combination regimens and cellular therapy represent promising directions forward in MPM research. There are several notable phase 3 trials of checkpoint inhibitors plus chemotherapy and targeted therapy going forward, plus intriguing data emerging on the potential role of chimeric antigen receptor (CAR) T-cell therapy in this setting.

One phase 3 trial to watch is IND277, which is comparing pembrolizumab plus cisplatin/pemetrexed chemotherapy to cisplatin/pemetrexed alone; that trial has enrolled 520 participants and has an estimated primary completion date in July 2022, according to the ClinicalTrials.gov website. Another is BEAT-Meso, a comparison of atezolizumab plus bevacizumab and chemotherapy against bevacizumab and chemotherapy, which has an estimated enrollment of 400 participants and primary completion date of January 2024. A third trial of interest is DREAM3R, which compares durvalumab plus chemotherapy followed by durvalumab maintenance to standard chemotherapy followed by observation. That study should enroll 480 participants and has an estimated primary completion date of April 2025.

CAR T-cell therapy, while best known for its emerging role in the treatment of hematologic malignancies, may also have a place in mesothelioma therapy one day. In a recently published report, investigators described a first-in-human phase I study of a mesothelin-targeted CAR T-cell therapy given in combination with pembrolizumab. Among 18 MPM patients who received pembrolizumab safely, median OS from time of CAR T-cell infusion was 23.9 months and 1-year OS was 83%, according to investigators.⁶An OS of nearly 24 months is “very encouraging” and compares favorably with historical results with systemic therapy in this difficult-to-treat disease, said Jacques P. Fontaine, MD, a thoracic surgeon and section head of mesothelioma research and treatment center at Moffitt Cancer Center in Tampa, Fla.

“It’s huge, but you have to take into account that this [OS] is still less than 2 years,” Dr. Fontaine said in an interview. “There’s still a lot of work to be done.”

Radiotherapy making an IMPRINT

Meanwhile, new developments in the multimodality treatment of resectable MPM are progressing and have the potential to extend survival among patients who undergo lung-sparing surgery.

Less aggressive intervention is increasingly the preferred approach to surgery in this patient population. That shift is supported by studies showing that lung-sparing pleurectomy-decortication (P/D) resulted in less morbidity and potentially better survival outcomes than extrapleural pneumonectomy (EPP), according to Andreas Rimner, MD, associate attending physician and director of thoracic radiation oncology research at Memorial Sloan Kettering Cancer Center in New York.

However, it is more challenging to deliver radiotherapy safely in patients who have undergone P/D as compared with patients who have undergone EPP, according to Dr. Rimner.

“When there’s no lung in place [as in EPP], it’s pretty simple – you just treat the entire empty chest to kill any microscopic cells that may still be left behind,” he said in an interview. “But now we have a situation where both lungs are still in place, and they are very radiation sensitive, so that’s not an easy feat.”

Driven by the limitations of conventional radiation, Dr. Rimner and colleagues developed a novel technique known as hemithoracic intensity-modulated pleural radiation therapy (IMPRINT) that allows more precise application of radiotherapy.

In a phase 2 study published in 2016, IMPRINT was found to be safe, with an acceptable rate of radiation pneumonitis (30% grade 2 or 3), according to investigators.⁷

Subsequent studies have demonstrated encouraging clinical outcomes, including a 20.2-month median OS for IMPRINT versus 12.3 months for conventional adjuvant radiotherapy in a retrospective study of 209 patients who underwent P/D between 1975 and 2015.⁸ Those findings led to the development of a phase 3 trial known as NRG-LU006 that is evaluating P/D plus chemotherapy with or without adjuvant IMPRINT in an estimated 150 patients. The study has a primary endpoint of OS, and an estimated primary completion date in July 2025, according to ClinicalTrials.gov.

Dr. Rimner said he’s optimistic about the prospects of this study, particularly with recently published results of a phase 3 study in which Italian investigators demonstrated an OS benefit of IMPRINT over palliative radiation in patients with nonmetastatic MPM.⁹

“That’s more data and rationale that shows there is good reason to believe that we are adding something here with this radiation technique,” said Dr. Rimner.

Dr. Fontaine, the thoracic surgeon and mesothelioma research head at Moffitt Cancer Center, said he’s hoping to see a substantial impact of IMPRINT on disease-free survival (DFS) once results of NRG-LU006 are available.

“I think DFS plays a role that we’ve underestimated over the last few years for sure,” he said.

For a patient with MPM, a short DFS can be anxiety provoking and may have negative impacts on quality of life, even despite a long OS, he explained.

“In terms of your outlook on life, how many times you have to go see a doctor, and how you enjoy life, there’s a big difference between the two,” he said.

Dr. Tsao provided disclosures related to Ariad, AstraZeneca, BMS, Boehringer Ingelheim, Eli Lilly, EMD Serono, Epizyme, Genentech, Huron, Merck, Millennium, Novartis, Polaris, Roche, Seattle Genetics, SELLAS Life Sciences Group, and Takeda. Dr. Fontaine reported no relevant disclosures. Dr. Rimner reported disclosures related to Bristol-Myers Squibb, GE Healthcare, Varian Medical Systems, and Boehringer Ingelheim.

References

1. Parikh K et al. Cancer Treat Rev. 2021 Sept 1;99:102250.

2. National Comprehensive Cancer Network (NCCN) Guidelines. Malignant Pleural Mesothelioma. Version 2.2021, published 2021 Feb 16. Accessed 2021 Aug 30. https://www.nccn.org/professionals/physician_gls/pdf/mpm.pdf

3. Popat S et al. Ann Oncol. 2020;31(12):1734-45.

4. Fennell D et al. Journal of Thoracic Oncology. 2021 Mar 1;16(3):S62.

5. Baas P et al. [published correction appears in Lancet. 2021 Feb 20;397(10275):670]. Lancet. 2021 Jan 30;397(10272):375-86.

6. Adusumilli PS et al. Cancer Discov. 2021 Jul 15;candisc.0407.2021.

7. Rimner A et al. J Clin Oncol. 2016;34(23):2761-8.

8. Shaikh F et al. J Thorac Oncol. 2017;12(6):993-1000.

9. Trovo M et al. Int J Radiat Oncol Biol Phys. 2021;109(5):1368-76.

The use of immune checkpoint inhibitors for cancer patients with advanced disease may be contradictory and cause more harm than good, according to a new study in JAMA Oncology.

The study, by Ravi B. Parikh, MD, an assistant professor of medical ethics and health policy and medicine at the University of Pennsylvania, Philadelphia, is an analysis of patient data from 280 U.S.-based community oncology practices. It included 34,131 patients who received first-line systemic therapy with immune checkpoint inhibitors (ICIs), or other treatment, between January 2014 and December 2019 for newly diagnosed metastatic or recurrent non–small cell lung cancer (NSCLC), urothelial cell cancer (UCC), renal cell cancer (RCC), or hepatocellular carcinoma (HCC). Researchers examined survival outcomes between patients who were eligible to participate in clinical trials with those who were deemed ineligible but may have still received ICIs.

For patients with poor performance status or organ dysfunction, participating in randomized clinical trials for immune checkpoint inhibitors is largely out of reach because of advanced disease, but it is not unusual for these patients to be accepted into clinical trials, a decision sometimes referred to as “desperation oncology,” the authors wrote.

In this study of 34,131 patients, 9,318 were considered ineligible to participate in ICI clinical trials because of advanced disease or organ dysfunction, yet up to 30% of these patients were treated with ICIs by their physician outside of a clinical trial. Dr. Parikh and colleagues found no overall survival differences between patients deemed ineligible for clinical trials, but were ultimately treated with ICI monotherapy, ICI combination therapy, or other treatments at 12 and 36 months. In fact, ICI monotherapy appeared to be harmful within 6 months of starting treatment.

“Clinicians who care for patients with poor performance status or organ dysfunction should be cautious about ICI use and carefully weigh expected survival gains against the potential for early mortality and adverse effects,” the authors wrote. They found the efficacy of ICI treatment alone, or in combination with other treatment, can be worse among trial-ineligible patients than patients who met the criteria for clinical trials.

No survival benefit was found for trial-ineligible patients who were treated with ICI monotherapy or combination therapy. Overall survival rates were similar at 12 and 36 months for both treatment groups. The overall median survival was less than 10 months, but 40% of trial ineligible patients treated with ICIs died within 6 months.

The use of ICIs for patients with poor performance status was found to be associated with lower hospice enrollment, more inpatient deaths, and more treatment during the last month of life. “It is critical to ensure that vulnerable, trial-ineligible patients are not exposed to non–evidence-based therapies that could cause harm and contradict patient goals,” the authors wrote.
 

The harms of treating unfit patients

The use of immune checkpoint inhibitor monotherapy in trial-ineligible patients is concerning, the authors said, because for patients with UCC and NSCLC, the standard of care is platinum-based chemotherapy. For patients with HCC and RCC, the standard of care is oral anti–vascular endothelial growth factor therapy. Immune checkpoint inhibitors may be prescribed in these cases to avoid side effects associated with other therapies, despite the lack of evidence showing that ICIs are effective in these cases.

“Individuals with poor performance status and/or organ dysfunction are vulnerable to receiving treatments that may not benefit them or cause disproportionately high side effects,” Dr. Parikh said in an interview. “Immunotherapy causes fewer side effects overall and is an attractive option, but there is no good phase 3 evidence that immunotherapy has benefits in this population.

“Physicians are preferentially using immunotherapy for unfit patients despite the fact that these individuals are usually excluded from clinical trials. Trial-ineligible patients – despite making up 30% of the cancer population – are different from patients studied in clinical trials. They are generally sicker, older and more prone to treatment adverse effects (including death), However, excluding these groups means that we don’t have good data on what treatments could benefit this vulnerable group. Thus, we are usually left to extrapolating results from healthier patients to unhealthy patients which risks giving them the wrong treatment,” he said.

A review that looked at immunotherapy in older adults suggested that, while those aged 65 or older represent most cancer patients, they are under-represented in clinical trials, including studies that led to approval of immunotherapy agents. A 2019 report suggested that, while 11 pivotal phase 3, randomized clinical trials have estimated the activity of ICIs in locally advanced and advanced NSCLC, each trial excluded patients with poor performance status.
 

Phase 3 trials needed for patients with poor performance

This retrospective study included 34,131 patients (median age, 70 years; 42% women) of which 27.3% had poor performance status and/or organ dysfunction and were classed as trial ineligible. The researchers assessed the use and overall survival outcomes following first-line ICI and non-ICI therapy that was initiated from January 2014 through December 2019.

Over the course of the study, the proportion of patients receiving ICI monotherapy increased from 0%-30.2% among trial-ineligible patients and from 0.1%-19.4% among eligible patients. However, among trial-ineligible patients, there were no overall survival differences between treatment with ICI monotherapy, ICI combination therapy and non-ICI therapy at 12 and 36 months.

Among trial-ineligible patients, ICI use was linked to a 14%-19% greater risk of death during the first 6 months after ICI initiation, but a 20% lower risk of death among those who survived 6 months after ICI initiation. Further, ICI combination therapy was associated with potential early harm among trial-ineligible patients.

“Phase 3 trials are sorely needed in patients with poor performance status or organ dysfunction so that we can adequately counsel patients who are unfit about expectations with novel cancer therapies,” Dr. Parikh said.

The cohort only included patients who received systemic therapy, which is a limitation of the study, so conclusions cannot be made about the efficacy of systemic therapy versus no systemic therapy in trial-ineligible patients.

Dr. Parikh reported nonfinancial support from Flatiron Health, grants from Humana, personal fees and equity from GNS Healthcare and Onc.AI, along with personal fees from the Cancer Study Group and Nanology outside the submitted work.

The use of immune checkpoint inhibitors for cancer patients with advanced disease may be contradictory and cause more harm than good, according to a new study in JAMA Oncology.

The study, by Ravi B. Parikh, MD, an assistant professor of medical ethics and health policy and medicine at the University of Pennsylvania, Philadelphia, is an analysis of patient data from 280 U.S.-based community oncology practices. It included 34,131 patients who received first-line systemic therapy with immune checkpoint inhibitors (ICIs), or other treatment, between January 2014 and December 2019 for newly diagnosed metastatic or recurrent non–small cell lung cancer (NSCLC), urothelial cell cancer (UCC), renal cell cancer (RCC), or hepatocellular carcinoma (HCC). Researchers examined survival outcomes between patients who were eligible to participate in clinical trials with those who were deemed ineligible but may have still received ICIs.

For patients with poor performance status or organ dysfunction, participating in randomized clinical trials for immune checkpoint inhibitors is largely out of reach because of advanced disease, but it is not unusual for these patients to be accepted into clinical trials, a decision sometimes referred to as “desperation oncology,” the authors wrote.

In this study of 34,131 patients, 9,318 were considered ineligible to participate in ICI clinical trials because of advanced disease or organ dysfunction, yet up to 30% of these patients were treated with ICIs by their physician outside of a clinical trial. Dr. Parikh and colleagues found no overall survival differences between patients deemed ineligible for clinical trials, but were ultimately treated with ICI monotherapy, ICI combination therapy, or other treatments at 12 and 36 months. In fact, ICI monotherapy appeared to be harmful within 6 months of starting treatment.

“Clinicians who care for patients with poor performance status or organ dysfunction should be cautious about ICI use and carefully weigh expected survival gains against the potential for early mortality and adverse effects,” the authors wrote. They found the efficacy of ICI treatment alone, or in combination with other treatment, can be worse among trial-ineligible patients than patients who met the criteria for clinical trials.

No survival benefit was found for trial-ineligible patients who were treated with ICI monotherapy or combination therapy. Overall survival rates were similar at 12 and 36 months for both treatment groups. The overall median survival was less than 10 months, but 40% of trial ineligible patients treated with ICIs died within 6 months.

The use of ICIs for patients with poor performance status was found to be associated with lower hospice enrollment, more inpatient deaths, and more treatment during the last month of life. “It is critical to ensure that vulnerable, trial-ineligible patients are not exposed to non–evidence-based therapies that could cause harm and contradict patient goals,” the authors wrote.
 

The harms of treating unfit patients

The use of immune checkpoint inhibitor monotherapy in trial-ineligible patients is concerning, the authors said, because for patients with UCC and NSCLC, the standard of care is platinum-based chemotherapy. For patients with HCC and RCC, the standard of care is oral anti–vascular endothelial growth factor therapy. Immune checkpoint inhibitors may be prescribed in these cases to avoid side effects associated with other therapies, despite the lack of evidence showing that ICIs are effective in these cases.

“Individuals with poor performance status and/or organ dysfunction are vulnerable to receiving treatments that may not benefit them or cause disproportionately high side effects,” Dr. Parikh said in an interview. “Immunotherapy causes fewer side effects overall and is an attractive option, but there is no good phase 3 evidence that immunotherapy has benefits in this population.

“Physicians are preferentially using immunotherapy for unfit patients despite the fact that these individuals are usually excluded from clinical trials. Trial-ineligible patients – despite making up 30% of the cancer population – are different from patients studied in clinical trials. They are generally sicker, older and more prone to treatment adverse effects (including death), However, excluding these groups means that we don’t have good data on what treatments could benefit this vulnerable group. Thus, we are usually left to extrapolating results from healthier patients to unhealthy patients which risks giving them the wrong treatment,” he said.

A review that looked at immunotherapy in older adults suggested that, while those aged 65 or older represent most cancer patients, they are under-represented in clinical trials, including studies that led to approval of immunotherapy agents. A 2019 report suggested that, while 11 pivotal phase 3, randomized clinical trials have estimated the activity of ICIs in locally advanced and advanced NSCLC, each trial excluded patients with poor performance status.
 

Phase 3 trials needed for patients with poor performance

This retrospective study included 34,131 patients (median age, 70 years; 42% women) of which 27.3% had poor performance status and/or organ dysfunction and were classed as trial ineligible. The researchers assessed the use and overall survival outcomes following first-line ICI and non-ICI therapy that was initiated from January 2014 through December 2019.

Over the course of the study, the proportion of patients receiving ICI monotherapy increased from 0%-30.2% among trial-ineligible patients and from 0.1%-19.4% among eligible patients. However, among trial-ineligible patients, there were no overall survival differences between treatment with ICI monotherapy, ICI combination therapy and non-ICI therapy at 12 and 36 months.

Among trial-ineligible patients, ICI use was linked to a 14%-19% greater risk of death during the first 6 months after ICI initiation, but a 20% lower risk of death among those who survived 6 months after ICI initiation. Further, ICI combination therapy was associated with potential early harm among trial-ineligible patients.

“Phase 3 trials are sorely needed in patients with poor performance status or organ dysfunction so that we can adequately counsel patients who are unfit about expectations with novel cancer therapies,” Dr. Parikh said.

The cohort only included patients who received systemic therapy, which is a limitation of the study, so conclusions cannot be made about the efficacy of systemic therapy versus no systemic therapy in trial-ineligible patients.

Dr. Parikh reported nonfinancial support from Flatiron Health, grants from Humana, personal fees and equity from GNS Healthcare and Onc.AI, along with personal fees from the Cancer Study Group and Nanology outside the submitted work.

The use of immune checkpoint inhibitors for cancer patients with advanced disease may be contradictory and cause more harm than good, according to a new study in JAMA Oncology.

The study, by Ravi B. Parikh, MD, an assistant professor of medical ethics and health policy and medicine at the University of Pennsylvania, Philadelphia, is an analysis of patient data from 280 U.S.-based community oncology practices. It included 34,131 patients who received first-line systemic therapy with immune checkpoint inhibitors (ICIs), or other treatment, between January 2014 and December 2019 for newly diagnosed metastatic or recurrent non–small cell lung cancer (NSCLC), urothelial cell cancer (UCC), renal cell cancer (RCC), or hepatocellular carcinoma (HCC). Researchers examined survival outcomes between patients who were eligible to participate in clinical trials with those who were deemed ineligible but may have still received ICIs.

For patients with poor performance status or organ dysfunction, participating in randomized clinical trials for immune checkpoint inhibitors is largely out of reach because of advanced disease, but it is not unusual for these patients to be accepted into clinical trials, a decision sometimes referred to as “desperation oncology,” the authors wrote.

In this study of 34,131 patients, 9,318 were considered ineligible to participate in ICI clinical trials because of advanced disease or organ dysfunction, yet up to 30% of these patients were treated with ICIs by their physician outside of a clinical trial. Dr. Parikh and colleagues found no overall survival differences between patients deemed ineligible for clinical trials, but were ultimately treated with ICI monotherapy, ICI combination therapy, or other treatments at 12 and 36 months. In fact, ICI monotherapy appeared to be harmful within 6 months of starting treatment.

“Clinicians who care for patients with poor performance status or organ dysfunction should be cautious about ICI use and carefully weigh expected survival gains against the potential for early mortality and adverse effects,” the authors wrote. They found the efficacy of ICI treatment alone, or in combination with other treatment, can be worse among trial-ineligible patients than patients who met the criteria for clinical trials.

No survival benefit was found for trial-ineligible patients who were treated with ICI monotherapy or combination therapy. Overall survival rates were similar at 12 and 36 months for both treatment groups. The overall median survival was less than 10 months, but 40% of trial ineligible patients treated with ICIs died within 6 months.

The use of ICIs for patients with poor performance status was found to be associated with lower hospice enrollment, more inpatient deaths, and more treatment during the last month of life. “It is critical to ensure that vulnerable, trial-ineligible patients are not exposed to non–evidence-based therapies that could cause harm and contradict patient goals,” the authors wrote.
 

The harms of treating unfit patients

The use of immune checkpoint inhibitor monotherapy in trial-ineligible patients is concerning, the authors said, because for patients with UCC and NSCLC, the standard of care is platinum-based chemotherapy. For patients with HCC and RCC, the standard of care is oral anti–vascular endothelial growth factor therapy. Immune checkpoint inhibitors may be prescribed in these cases to avoid side effects associated with other therapies, despite the lack of evidence showing that ICIs are effective in these cases.

“Individuals with poor performance status and/or organ dysfunction are vulnerable to receiving treatments that may not benefit them or cause disproportionately high side effects,” Dr. Parikh said in an interview. “Immunotherapy causes fewer side effects overall and is an attractive option, but there is no good phase 3 evidence that immunotherapy has benefits in this population.

“Physicians are preferentially using immunotherapy for unfit patients despite the fact that these individuals are usually excluded from clinical trials. Trial-ineligible patients – despite making up 30% of the cancer population – are different from patients studied in clinical trials. They are generally sicker, older and more prone to treatment adverse effects (including death), However, excluding these groups means that we don’t have good data on what treatments could benefit this vulnerable group. Thus, we are usually left to extrapolating results from healthier patients to unhealthy patients which risks giving them the wrong treatment,” he said.

A review that looked at immunotherapy in older adults suggested that, while those aged 65 or older represent most cancer patients, they are under-represented in clinical trials, including studies that led to approval of immunotherapy agents. A 2019 report suggested that, while 11 pivotal phase 3, randomized clinical trials have estimated the activity of ICIs in locally advanced and advanced NSCLC, each trial excluded patients with poor performance status.
 

Phase 3 trials needed for patients with poor performance

This retrospective study included 34,131 patients (median age, 70 years; 42% women) of which 27.3% had poor performance status and/or organ dysfunction and were classed as trial ineligible. The researchers assessed the use and overall survival outcomes following first-line ICI and non-ICI therapy that was initiated from January 2014 through December 2019.

Over the course of the study, the proportion of patients receiving ICI monotherapy increased from 0%-30.2% among trial-ineligible patients and from 0.1%-19.4% among eligible patients. However, among trial-ineligible patients, there were no overall survival differences between treatment with ICI monotherapy, ICI combination therapy and non-ICI therapy at 12 and 36 months.

Among trial-ineligible patients, ICI use was linked to a 14%-19% greater risk of death during the first 6 months after ICI initiation, but a 20% lower risk of death among those who survived 6 months after ICI initiation. Further, ICI combination therapy was associated with potential early harm among trial-ineligible patients.

“Phase 3 trials are sorely needed in patients with poor performance status or organ dysfunction so that we can adequately counsel patients who are unfit about expectations with novel cancer therapies,” Dr. Parikh said.

The cohort only included patients who received systemic therapy, which is a limitation of the study, so conclusions cannot be made about the efficacy of systemic therapy versus no systemic therapy in trial-ineligible patients.

Dr. Parikh reported nonfinancial support from Flatiron Health, grants from Humana, personal fees and equity from GNS Healthcare and Onc.AI, along with personal fees from the Cancer Study Group and Nanology outside the submitted work.

Aspirin use was associated with longer overall survival in people with inoperable non–small cell lung cancer (NSCLC), according to a new study from Taiwan.

copyright Darren Hester/Fotolia.com

The analysis, published online Nov. 22 in BMC Cancer , adds another data point to a small and inconsistent evidence base.

“Despite the need for future prospective randomized clinical trials, aspirin may be considered as an additional treatment for inoperable NSCLC patients,” Ming-Szu Hung, MD, of Chang-Gung University, Taoyuan City, and colleagues write.

The current literature suggests that the over-the-counter medication may help ward off various types of cancer, including lung cancer, but the various study findings do not always align. For lung-cancer survival, in particular, a few observational studies have found increased survival among aspirin users while others have not.

To help bring clarity to the literature, Dr. Hung’s team examined data from Taiwan’s National Health Insurance Research Database on more than 38,000 patients diagnosed with NSCLC between 2000 and 2012, almost 5,000 of whom were taking aspirin at the time of diagnosis.

The researchers found that aspirin users survived for a median of 1.73 years, compared with 1.30 years for nonusers. Taking the drug was associated with longer overall survival in time-varying covariate analysis (hazard ratio, 0.83; 95% CI, 0.80-0.86). This finding was confirmed in a propensity-score analysis of 4,932 matched pairs (HR, 0.79; 95% CI, 0.75-0.83).

“These results warrant further randomized clinical trials to evaluate the actual role of aspirin in the treatment of NSCLC patients,” the researchers conclude.

But Úna McMenamin, PhD, a cancer epidemiologist at Queen’s University Belfast, Ireland, was not convinced by the study’s methods.

While she praised its large size and use of population-based health registers, she expressed concern about the potential for reverse causation, “as it is unclear whether authors lagged the aspirin exposure in the cohort of lung cancer patients.”

There is evidence that common medications such as aspirin may be withdrawn from patients who are thought to be near the end of their life, Dr. McMenamin told this news organization. When not factored into the statistical analysis, aspirin may appear “to be spuriously associated with a reduced risk of death when, in fact, no association may be present.”

Previous studies of aspirin use in lung cancer patients that have included a lag, such as one Dr. McMenamin and colleagues conducted in 2015, have found no evidence of a protective effect.

That is why, according to Dr. McMenamin, “additional population-based studies, in diverse populations, are required to investigate the association between aspirin use and survival outcomes in lung-cancer patients to determine whether randomized controlled trials are warranted in this patient group.”

In addition, she noted, “any potential benefit of aspirin in lung cancer patients needs to be balanced against known adverse events associated with prolonged aspirin use, such as gastrointestinal bleeding.”

Dr. Hung did not reply to requests for comment.

The study had no funding, and the researchers report no conflicts of interest.

A version of this article first appeared on Medscape.com.

Aspirin use was associated with longer overall survival in people with inoperable non–small cell lung cancer (NSCLC), according to a new study from Taiwan.

copyright Darren Hester/Fotolia.com

The analysis, published online Nov. 22 in BMC Cancer , adds another data point to a small and inconsistent evidence base.

“Despite the need for future prospective randomized clinical trials, aspirin may be considered as an additional treatment for inoperable NSCLC patients,” Ming-Szu Hung, MD, of Chang-Gung University, Taoyuan City, and colleagues write.

The current literature suggests that the over-the-counter medication may help ward off various types of cancer, including lung cancer, but the various study findings do not always align. For lung-cancer survival, in particular, a few observational studies have found increased survival among aspirin users while others have not.

To help bring clarity to the literature, Dr. Hung’s team examined data from Taiwan’s National Health Insurance Research Database on more than 38,000 patients diagnosed with NSCLC between 2000 and 2012, almost 5,000 of whom were taking aspirin at the time of diagnosis.

The researchers found that aspirin users survived for a median of 1.73 years, compared with 1.30 years for nonusers. Taking the drug was associated with longer overall survival in time-varying covariate analysis (hazard ratio, 0.83; 95% CI, 0.80-0.86). This finding was confirmed in a propensity-score analysis of 4,932 matched pairs (HR, 0.79; 95% CI, 0.75-0.83).

“These results warrant further randomized clinical trials to evaluate the actual role of aspirin in the treatment of NSCLC patients,” the researchers conclude.

But Úna McMenamin, PhD, a cancer epidemiologist at Queen’s University Belfast, Ireland, was not convinced by the study’s methods.

While she praised its large size and use of population-based health registers, she expressed concern about the potential for reverse causation, “as it is unclear whether authors lagged the aspirin exposure in the cohort of lung cancer patients.”

There is evidence that common medications such as aspirin may be withdrawn from patients who are thought to be near the end of their life, Dr. McMenamin told this news organization. When not factored into the statistical analysis, aspirin may appear “to be spuriously associated with a reduced risk of death when, in fact, no association may be present.”

Previous studies of aspirin use in lung cancer patients that have included a lag, such as one Dr. McMenamin and colleagues conducted in 2015, have found no evidence of a protective effect.

That is why, according to Dr. McMenamin, “additional population-based studies, in diverse populations, are required to investigate the association between aspirin use and survival outcomes in lung-cancer patients to determine whether randomized controlled trials are warranted in this patient group.”

In addition, she noted, “any potential benefit of aspirin in lung cancer patients needs to be balanced against known adverse events associated with prolonged aspirin use, such as gastrointestinal bleeding.”

Dr. Hung did not reply to requests for comment.

The study had no funding, and the researchers report no conflicts of interest.

A version of this article first appeared on Medscape.com.

Aspirin use was associated with longer overall survival in people with inoperable non–small cell lung cancer (NSCLC), according to a new study from Taiwan.

copyright Darren Hester/Fotolia.com

The analysis, published online Nov. 22 in BMC Cancer , adds another data point to a small and inconsistent evidence base.

“Despite the need for future prospective randomized clinical trials, aspirin may be considered as an additional treatment for inoperable NSCLC patients,” Ming-Szu Hung, MD, of Chang-Gung University, Taoyuan City, and colleagues write.

The current literature suggests that the over-the-counter medication may help ward off various types of cancer, including lung cancer, but the various study findings do not always align. For lung-cancer survival, in particular, a few observational studies have found increased survival among aspirin users while others have not.

To help bring clarity to the literature, Dr. Hung’s team examined data from Taiwan’s National Health Insurance Research Database on more than 38,000 patients diagnosed with NSCLC between 2000 and 2012, almost 5,000 of whom were taking aspirin at the time of diagnosis.

The researchers found that aspirin users survived for a median of 1.73 years, compared with 1.30 years for nonusers. Taking the drug was associated with longer overall survival in time-varying covariate analysis (hazard ratio, 0.83; 95% CI, 0.80-0.86). This finding was confirmed in a propensity-score analysis of 4,932 matched pairs (HR, 0.79; 95% CI, 0.75-0.83).

“These results warrant further randomized clinical trials to evaluate the actual role of aspirin in the treatment of NSCLC patients,” the researchers conclude.

But Úna McMenamin, PhD, a cancer epidemiologist at Queen’s University Belfast, Ireland, was not convinced by the study’s methods.

While she praised its large size and use of population-based health registers, she expressed concern about the potential for reverse causation, “as it is unclear whether authors lagged the aspirin exposure in the cohort of lung cancer patients.”

There is evidence that common medications such as aspirin may be withdrawn from patients who are thought to be near the end of their life, Dr. McMenamin told this news organization. When not factored into the statistical analysis, aspirin may appear “to be spuriously associated with a reduced risk of death when, in fact, no association may be present.”

Previous studies of aspirin use in lung cancer patients that have included a lag, such as one Dr. McMenamin and colleagues conducted in 2015, have found no evidence of a protective effect.

That is why, according to Dr. McMenamin, “additional population-based studies, in diverse populations, are required to investigate the association between aspirin use and survival outcomes in lung-cancer patients to determine whether randomized controlled trials are warranted in this patient group.”

In addition, she noted, “any potential benefit of aspirin in lung cancer patients needs to be balanced against known adverse events associated with prolonged aspirin use, such as gastrointestinal bleeding.”

Dr. Hung did not reply to requests for comment.

The study had no funding, and the researchers report no conflicts of interest.

A version of this article first appeared on Medscape.com.

The diagnosis is squamous cell carcinoma. A central or hilar mass is most likely to be a squamous cell carcinoma or a small cell tumor and less commonly an adenocarcinoma. Histologically, when there is lack of cohesion among the epithelial cells due to malignant changes, the cells get arranged in a concentric manner. The fate of a squamous cell is to form keratin, so these cells lay down keratin in a concentric manner and then appear as keratin pearls. 

This patient's tumor is found to have programmed cell death–ligand 1 ≥ 1% and has no actionable molecular markers. The patient has a performance status score of 1. In a patient with advanced or metastatic squamous cell carcinoma with a performance status score of 1, the National Comprehensive Cancer Network recommends pembrolizumab/carboplatin/paclitaxel or pembrolizumab/carboplatin/albumin-bound paclitaxel as preferred regimens. The pembrolizumab component is based on the results of the KEYNOTE-407 trial. In patients with previously untreated metastatic, squamous non-small cell lung cancer, the addition of pembrolizumab to chemotherapy with carboplatin plus paclitaxel or nab-paclitaxel resulted in significantly longer overall survival and progression-free survival than chemotherapy alone.

Maurie Markman, MD, President, Department of Medical Oncology, Cancer Treatment Centers of America.

Maurie Markman, MD, has disclosed the following relevant financial relationships:

Serve(d) as a director, officer, partner, employee, advisor, consultant, or trustee for: Merck
Serve(d) as a speaker or a member of a speakers bureau for: AstraZeneca; Novis; Glaxo Smith Kline
Received research grant from: AstraZeneca; Novis; GSK; Merck

The diagnosis is squamous cell carcinoma. A central or hilar mass is most likely to be a squamous cell carcinoma or a small cell tumor and less commonly an adenocarcinoma. Histologically, when there is lack of cohesion among the epithelial cells due to malignant changes, the cells get arranged in a concentric manner. The fate of a squamous cell is to form keratin, so these cells lay down keratin in a concentric manner and then appear as keratin pearls. 

This patient's tumor is found to have programmed cell death–ligand 1 ≥ 1% and has no actionable molecular markers. The patient has a performance status score of 1. In a patient with advanced or metastatic squamous cell carcinoma with a performance status score of 1, the National Comprehensive Cancer Network recommends pembrolizumab/carboplatin/paclitaxel or pembrolizumab/carboplatin/albumin-bound paclitaxel as preferred regimens. The pembrolizumab component is based on the results of the KEYNOTE-407 trial. In patients with previously untreated metastatic, squamous non-small cell lung cancer, the addition of pembrolizumab to chemotherapy with carboplatin plus paclitaxel or nab-paclitaxel resulted in significantly longer overall survival and progression-free survival than chemotherapy alone.

Maurie Markman, MD, President, Department of Medical Oncology, Cancer Treatment Centers of America.

Maurie Markman, MD, has disclosed the following relevant financial relationships:

Serve(d) as a director, officer, partner, employee, advisor, consultant, or trustee for: Merck
Serve(d) as a speaker or a member of a speakers bureau for: AstraZeneca; Novis; Glaxo Smith Kline
Received research grant from: AstraZeneca; Novis; GSK; Merck

The diagnosis is squamous cell carcinoma. A central or hilar mass is most likely to be a squamous cell carcinoma or a small cell tumor and less commonly an adenocarcinoma. Histologically, when there is lack of cohesion among the epithelial cells due to malignant changes, the cells get arranged in a concentric manner. The fate of a squamous cell is to form keratin, so these cells lay down keratin in a concentric manner and then appear as keratin pearls. 

This patient's tumor is found to have programmed cell death–ligand 1 ≥ 1% and has no actionable molecular markers. The patient has a performance status score of 1. In a patient with advanced or metastatic squamous cell carcinoma with a performance status score of 1, the National Comprehensive Cancer Network recommends pembrolizumab/carboplatin/paclitaxel or pembrolizumab/carboplatin/albumin-bound paclitaxel as preferred regimens. The pembrolizumab component is based on the results of the KEYNOTE-407 trial. In patients with previously untreated metastatic, squamous non-small cell lung cancer, the addition of pembrolizumab to chemotherapy with carboplatin plus paclitaxel or nab-paclitaxel resulted in significantly longer overall survival and progression-free survival than chemotherapy alone.

Maurie Markman, MD, President, Department of Medical Oncology, Cancer Treatment Centers of America.

Maurie Markman, MD, has disclosed the following relevant financial relationships:

Serve(d) as a director, officer, partner, employee, advisor, consultant, or trustee for: Merck
Serve(d) as a speaker or a member of a speakers bureau for: AstraZeneca; Novis; Glaxo Smith Kline
Received research grant from: AstraZeneca; Novis; GSK; Merck