How to watch – and when to biopsy – atypical nevi

CHICAGO – Among the many difficult decisions dermatologists have to make, some of the more challenging involve caring for patients with atypical melanocytic lesions. A session at the summer meeting of the American Academy of Dermatology provided some guidance for surveillance of these patients.

Caroline C. Kim, MD, directs the pigmented lesion clinic at Beth Israel Deaconess Medical Center, Boston, and shared the evidence base for her management schema, along with some clinical pearls. No dermatologist ever wants to miss a melanoma, she acknowledged. “We want to avoid those scenarios but not make people feel like Swiss cheese” from multiple biopsies, she said during her presentation.

One key concept that can help physicians find the balance, she said, is that although the presence of atypical or dysplastic nevi increases the risk for melanoma in a given patient, the actual transformation rate of dysplastic nevi to melanomas is not known. In fact, she said, between 50% and 75% of melanomas may arise de novo.

From a dermatopathologic perspective, nevi exist along a continuum of mild to moderate to severe dysplasia, and some lesions are melanomas. But mildly dysplastic nevi are not fated to continue a transformation to increasingly severely dysplastic ones, or to melanomas.

Bringing these ideas to the patient discussion means that one should avoid ever calling a dysplastic nevus “precancerous,” said Dr. Kim; not only is this inaccurate, but it is unnecessarily anxiety provoking, she said.

Within this framework, the initial exam can begin with a search for signature patterns – and ugly ducklings. Each patient will have a pattern, or several patterns, that typify their nevi. Though the markings may be “atypical,” they’ll have some consistency; if the nevus has several neighbors that look just like it, it’s much less likely to be melanoma. “If they are matching partners, it’s more likely that it’s your typical nevus pattern,” said Dr. Kim, also an assistant professor of dermatology at Harvard Medical School, Boston.

By contrast, some lesions stand out from the patient’s other atypical nevi. They may be larger, darker, more elevated, but sometimes, “Even from the doorway, they just stand out,” Dr. Kim said. And these dual concepts of signature patterns and ugly ducklings are useful to talk over with patients, she said. “It’s so easy for patients to grab on to – they totally get it.”

“Use dermoscopy” when you get to the detailed skin exam, she said. “Data have shown that as clinicians, we are pretty good at picking up melanomas ... But with dermoscopy, our detection rate goes up to 70%-95%,” Dr. Kim said. The caveat is that dermoscopy without proper training is a dangerous tool: Several studies have shown that melanoma detection rates drop compared to the naked eye when dermoscopy is performed by untrained users, she said. “Training matters.”

A further tool to help train the eye and mind to recognize benign and malignant patterns when performing dermoscopy of atypical nevi is a now-classic paper that maps these patterns out, she said (Dermatol Surg. 2007;33[11]:1388-91).

“Beware of de novo and changing lesions,” Dr. Kim said. “A picture truly is worth a thousand words” for tracking these, she said.

Total body digital photography, if it’s available, is the best way to track subtle changes, and to spot new lesions as they crop up, said Dr. Kim. In head-to-head studies with dermoscopy and visual exam alone, digital photography can reduce the number of lesions excised, detect early melanoma, and reduce patient anxiety. One study found a 3.8-fold reduction in the mean rate of nevus biopsies when total body digital photography was used, she said (J Am Acad Dermatol. 2016 Mar. doi: 10.1016/j.jaad.2016.02.1152).

A patient care pearl Dr. Kim shared is that she’ll ask patients for their smartphones and take a photograph of the patients’ backs with those phones. This lets them have a handy reference image for monitoring their own skin in the intervals between visits. But make sure, she said, that patients know that “all change is not bad change – you can get new nevi through your 50s.

“Consider sharing care with a local pigmented lesion clinic” if digital photography is not available at your site, said Dr. Kim. She does this for several of her patients, alternating visits with the primary dermatologist.

When should you perform a biopsy?

“You don’t need to biopsy an atypical nevus to call it atypical. You biopsy lesions if you’re suspicious for calling it melanoma,” Dr. Kim said. Removal also can be considered if, for example, a patient lives alone and the nevi of concern are on her back so home monitoring is a challenge, she said.

Once you’ve decided to biopsy, a narrow excisional biopsy with saucerization and 1- to 3-mm margins is preferred when there’s a high suspicion for melanoma, said Dr. Kim, citing a study that found that 2-mm margins using this method yielded an 87% rate of clear pathologic specimen margins in dysplastic nevi (J Am Acad Dermatol. 2017 Dec;77[6]:1096-9). There is some leeway in the guidelines, but “the preferred technique is a narrow excisional biopsy when you are worried,” she said.

There may be times when a partial or incisional biopsy is a rational choice, as when lesions are very large, located on the face or acral areas, or when suspicion for melanoma is low. “If you do partial biopsies, you really have to be aware of the limitations” of the technique since it may miss the nidus of melanoma within an otherwise bland lesion, Dr. Kim pointed out.

And don’t forget to plan your closure with future follow-up in mind: Dr. Kim related that she’d seen a patient for melanoma who’d had the large excisional biopsy performed elsewhere; the patient’s site was closed with an advancement flap, which made sentinel node biopsy impossible.

When the results come back, then what?

Studies have found that atypical nevi are characterized differently at different sites and that management strategies vary geographically, Dr. Kim said. “There’s a need for large-scale data to further investigate the role of observation versus re-excision of dysplastic nevi,” and a multicenter study is underway to do just that, she said, under the auspices of the Pigmented Lesion Subcommittee of the Melanoma Prevention Working Group (ECOG/SWOG).

That same subcommittee has issued a consensus statement for dealing with histologically positive excisional biopsy margins. For mildly dysplastic lesions without clinically observable residual pigment, observation is preferred. Severely dysplastic lesions with unpigmented margins should be re-excised, says the statement (JAMA Dermatol. 2015;151[2]:212-18).

For the intermediate lesions, the group recommended that a reasonable option is to observe a moderately dysplastic nevus site that’s been excisionally biopsied with a finding of positive margins, while acknowledging that more data are needed.

All biopsy sites should be followed for regrowth, though recurrence of pigment alone doesn’t necessarily mean another excision is in the patient’s future, Dr. Kim said.

She reported no conflicts of interest.

koakes@mdedge.com

SOURCE: Kim C. Summer AAD 2018, Presentation F014.

CHICAGO – Among the many difficult decisions dermatologists have to make, some of the more challenging involve caring for patients with atypical melanocytic lesions. A session at the summer meeting of the American Academy of Dermatology provided some guidance for surveillance of these patients.

Caroline C. Kim, MD, directs the pigmented lesion clinic at Beth Israel Deaconess Medical Center, Boston, and shared the evidence base for her management schema, along with some clinical pearls. No dermatologist ever wants to miss a melanoma, she acknowledged. “We want to avoid those scenarios but not make people feel like Swiss cheese” from multiple biopsies, she said during her presentation.

One key concept that can help physicians find the balance, she said, is that although the presence of atypical or dysplastic nevi increases the risk for melanoma in a given patient, the actual transformation rate of dysplastic nevi to melanomas is not known. In fact, she said, between 50% and 75% of melanomas may arise de novo.

From a dermatopathologic perspective, nevi exist along a continuum of mild to moderate to severe dysplasia, and some lesions are melanomas. But mildly dysplastic nevi are not fated to continue a transformation to increasingly severely dysplastic ones, or to melanomas.

Bringing these ideas to the patient discussion means that one should avoid ever calling a dysplastic nevus “precancerous,” said Dr. Kim; not only is this inaccurate, but it is unnecessarily anxiety provoking, she said.

Within this framework, the initial exam can begin with a search for signature patterns – and ugly ducklings. Each patient will have a pattern, or several patterns, that typify their nevi. Though the markings may be “atypical,” they’ll have some consistency; if the nevus has several neighbors that look just like it, it’s much less likely to be melanoma. “If they are matching partners, it’s more likely that it’s your typical nevus pattern,” said Dr. Kim, also an assistant professor of dermatology at Harvard Medical School, Boston.

By contrast, some lesions stand out from the patient’s other atypical nevi. They may be larger, darker, more elevated, but sometimes, “Even from the doorway, they just stand out,” Dr. Kim said. And these dual concepts of signature patterns and ugly ducklings are useful to talk over with patients, she said. “It’s so easy for patients to grab on to – they totally get it.”

“Use dermoscopy” when you get to the detailed skin exam, she said. “Data have shown that as clinicians, we are pretty good at picking up melanomas ... But with dermoscopy, our detection rate goes up to 70%-95%,” Dr. Kim said. The caveat is that dermoscopy without proper training is a dangerous tool: Several studies have shown that melanoma detection rates drop compared to the naked eye when dermoscopy is performed by untrained users, she said. “Training matters.”

A further tool to help train the eye and mind to recognize benign and malignant patterns when performing dermoscopy of atypical nevi is a now-classic paper that maps these patterns out, she said (Dermatol Surg. 2007;33[11]:1388-91).

“Beware of de novo and changing lesions,” Dr. Kim said. “A picture truly is worth a thousand words” for tracking these, she said.

Total body digital photography, if it’s available, is the best way to track subtle changes, and to spot new lesions as they crop up, said Dr. Kim. In head-to-head studies with dermoscopy and visual exam alone, digital photography can reduce the number of lesions excised, detect early melanoma, and reduce patient anxiety. One study found a 3.8-fold reduction in the mean rate of nevus biopsies when total body digital photography was used, she said (J Am Acad Dermatol. 2016 Mar. doi: 10.1016/j.jaad.2016.02.1152).

A patient care pearl Dr. Kim shared is that she’ll ask patients for their smartphones and take a photograph of the patients’ backs with those phones. This lets them have a handy reference image for monitoring their own skin in the intervals between visits. But make sure, she said, that patients know that “all change is not bad change – you can get new nevi through your 50s.

“Consider sharing care with a local pigmented lesion clinic” if digital photography is not available at your site, said Dr. Kim. She does this for several of her patients, alternating visits with the primary dermatologist.

When should you perform a biopsy?

“You don’t need to biopsy an atypical nevus to call it atypical. You biopsy lesions if you’re suspicious for calling it melanoma,” Dr. Kim said. Removal also can be considered if, for example, a patient lives alone and the nevi of concern are on her back so home monitoring is a challenge, she said.

Once you’ve decided to biopsy, a narrow excisional biopsy with saucerization and 1- to 3-mm margins is preferred when there’s a high suspicion for melanoma, said Dr. Kim, citing a study that found that 2-mm margins using this method yielded an 87% rate of clear pathologic specimen margins in dysplastic nevi (J Am Acad Dermatol. 2017 Dec;77[6]:1096-9). There is some leeway in the guidelines, but “the preferred technique is a narrow excisional biopsy when you are worried,” she said.

There may be times when a partial or incisional biopsy is a rational choice, as when lesions are very large, located on the face or acral areas, or when suspicion for melanoma is low. “If you do partial biopsies, you really have to be aware of the limitations” of the technique since it may miss the nidus of melanoma within an otherwise bland lesion, Dr. Kim pointed out.

And don’t forget to plan your closure with future follow-up in mind: Dr. Kim related that she’d seen a patient for melanoma who’d had the large excisional biopsy performed elsewhere; the patient’s site was closed with an advancement flap, which made sentinel node biopsy impossible.

When the results come back, then what?

Studies have found that atypical nevi are characterized differently at different sites and that management strategies vary geographically, Dr. Kim said. “There’s a need for large-scale data to further investigate the role of observation versus re-excision of dysplastic nevi,” and a multicenter study is underway to do just that, she said, under the auspices of the Pigmented Lesion Subcommittee of the Melanoma Prevention Working Group (ECOG/SWOG).

That same subcommittee has issued a consensus statement for dealing with histologically positive excisional biopsy margins. For mildly dysplastic lesions without clinically observable residual pigment, observation is preferred. Severely dysplastic lesions with unpigmented margins should be re-excised, says the statement (JAMA Dermatol. 2015;151[2]:212-18).

For the intermediate lesions, the group recommended that a reasonable option is to observe a moderately dysplastic nevus site that’s been excisionally biopsied with a finding of positive margins, while acknowledging that more data are needed.

All biopsy sites should be followed for regrowth, though recurrence of pigment alone doesn’t necessarily mean another excision is in the patient’s future, Dr. Kim said.

She reported no conflicts of interest.

koakes@mdedge.com

SOURCE: Kim C. Summer AAD 2018, Presentation F014.

CHICAGO – Among the many difficult decisions dermatologists have to make, some of the more challenging involve caring for patients with atypical melanocytic lesions. A session at the summer meeting of the American Academy of Dermatology provided some guidance for surveillance of these patients.

Caroline C. Kim, MD, directs the pigmented lesion clinic at Beth Israel Deaconess Medical Center, Boston, and shared the evidence base for her management schema, along with some clinical pearls. No dermatologist ever wants to miss a melanoma, she acknowledged. “We want to avoid those scenarios but not make people feel like Swiss cheese” from multiple biopsies, she said during her presentation.

One key concept that can help physicians find the balance, she said, is that although the presence of atypical or dysplastic nevi increases the risk for melanoma in a given patient, the actual transformation rate of dysplastic nevi to melanomas is not known. In fact, she said, between 50% and 75% of melanomas may arise de novo.

From a dermatopathologic perspective, nevi exist along a continuum of mild to moderate to severe dysplasia, and some lesions are melanomas. But mildly dysplastic nevi are not fated to continue a transformation to increasingly severely dysplastic ones, or to melanomas.

Bringing these ideas to the patient discussion means that one should avoid ever calling a dysplastic nevus “precancerous,” said Dr. Kim; not only is this inaccurate, but it is unnecessarily anxiety provoking, she said.

Within this framework, the initial exam can begin with a search for signature patterns – and ugly ducklings. Each patient will have a pattern, or several patterns, that typify their nevi. Though the markings may be “atypical,” they’ll have some consistency; if the nevus has several neighbors that look just like it, it’s much less likely to be melanoma. “If they are matching partners, it’s more likely that it’s your typical nevus pattern,” said Dr. Kim, also an assistant professor of dermatology at Harvard Medical School, Boston.

By contrast, some lesions stand out from the patient’s other atypical nevi. They may be larger, darker, more elevated, but sometimes, “Even from the doorway, they just stand out,” Dr. Kim said. And these dual concepts of signature patterns and ugly ducklings are useful to talk over with patients, she said. “It’s so easy for patients to grab on to – they totally get it.”

“Use dermoscopy” when you get to the detailed skin exam, she said. “Data have shown that as clinicians, we are pretty good at picking up melanomas ... But with dermoscopy, our detection rate goes up to 70%-95%,” Dr. Kim said. The caveat is that dermoscopy without proper training is a dangerous tool: Several studies have shown that melanoma detection rates drop compared to the naked eye when dermoscopy is performed by untrained users, she said. “Training matters.”

A further tool to help train the eye and mind to recognize benign and malignant patterns when performing dermoscopy of atypical nevi is a now-classic paper that maps these patterns out, she said (Dermatol Surg. 2007;33[11]:1388-91).

“Beware of de novo and changing lesions,” Dr. Kim said. “A picture truly is worth a thousand words” for tracking these, she said.

Total body digital photography, if it’s available, is the best way to track subtle changes, and to spot new lesions as they crop up, said Dr. Kim. In head-to-head studies with dermoscopy and visual exam alone, digital photography can reduce the number of lesions excised, detect early melanoma, and reduce patient anxiety. One study found a 3.8-fold reduction in the mean rate of nevus biopsies when total body digital photography was used, she said (J Am Acad Dermatol. 2016 Mar. doi: 10.1016/j.jaad.2016.02.1152).

A patient care pearl Dr. Kim shared is that she’ll ask patients for their smartphones and take a photograph of the patients’ backs with those phones. This lets them have a handy reference image for monitoring their own skin in the intervals between visits. But make sure, she said, that patients know that “all change is not bad change – you can get new nevi through your 50s.

“Consider sharing care with a local pigmented lesion clinic” if digital photography is not available at your site, said Dr. Kim. She does this for several of her patients, alternating visits with the primary dermatologist.

When should you perform a biopsy?

“You don’t need to biopsy an atypical nevus to call it atypical. You biopsy lesions if you’re suspicious for calling it melanoma,” Dr. Kim said. Removal also can be considered if, for example, a patient lives alone and the nevi of concern are on her back so home monitoring is a challenge, she said.

Once you’ve decided to biopsy, a narrow excisional biopsy with saucerization and 1- to 3-mm margins is preferred when there’s a high suspicion for melanoma, said Dr. Kim, citing a study that found that 2-mm margins using this method yielded an 87% rate of clear pathologic specimen margins in dysplastic nevi (J Am Acad Dermatol. 2017 Dec;77[6]:1096-9). There is some leeway in the guidelines, but “the preferred technique is a narrow excisional biopsy when you are worried,” she said.

There may be times when a partial or incisional biopsy is a rational choice, as when lesions are very large, located on the face or acral areas, or when suspicion for melanoma is low. “If you do partial biopsies, you really have to be aware of the limitations” of the technique since it may miss the nidus of melanoma within an otherwise bland lesion, Dr. Kim pointed out.

And don’t forget to plan your closure with future follow-up in mind: Dr. Kim related that she’d seen a patient for melanoma who’d had the large excisional biopsy performed elsewhere; the patient’s site was closed with an advancement flap, which made sentinel node biopsy impossible.

When the results come back, then what?

Studies have found that atypical nevi are characterized differently at different sites and that management strategies vary geographically, Dr. Kim said. “There’s a need for large-scale data to further investigate the role of observation versus re-excision of dysplastic nevi,” and a multicenter study is underway to do just that, she said, under the auspices of the Pigmented Lesion Subcommittee of the Melanoma Prevention Working Group (ECOG/SWOG).

That same subcommittee has issued a consensus statement for dealing with histologically positive excisional biopsy margins. For mildly dysplastic lesions without clinically observable residual pigment, observation is preferred. Severely dysplastic lesions with unpigmented margins should be re-excised, says the statement (JAMA Dermatol. 2015;151[2]:212-18).

For the intermediate lesions, the group recommended that a reasonable option is to observe a moderately dysplastic nevus site that’s been excisionally biopsied with a finding of positive margins, while acknowledging that more data are needed.

All biopsy sites should be followed for regrowth, though recurrence of pigment alone doesn’t necessarily mean another excision is in the patient’s future, Dr. Kim said.

She reported no conflicts of interest.

koakes@mdedge.com

SOURCE: Kim C. Summer AAD 2018, Presentation F014.