Although treatment for dysplastic nevi varies among dermatologists, these atypical moles are always biopsied, and then patients are followed closely to watch for melanomas, according to an expert.
Dallas - Although treatment for dysplastic nevi varies among dermatologists, these atypical moles are always biopsied, and then patients are followed closely to watch for melanoma, according to Terry L. Barrett, M.D., dermatopathologist, director, dermatopathology and podiatric pathology, ProPath Dermatopathology, Dallas.
Those who have dysplastic nevi and a family history of melanoma (two or more close blood relatives with the disease) have an increased risk of developing melanoma. Individuals who have dysplastic nevi, but no family history of melanoma, face a seven to 27 times higher risk of developing melanoma compared to the general population, according to the Skin Cancer Foundation.
"These moles are very common," Dr. Barrett explains. "At our pathology practice, we have eight dermatopathologists and we see probably 50 to 100 a day of these lesions."
Consensus for treatment
At the 1991 Consensus Conference for Dysplastic Nevi, the recommendation was made not to use the dysplastic nevus as a sign-out diagnosis or in the pathology reports, because dysplasia indicates that this is a premalignant lesion, and left untreated may evolve into melanoma, and this was found to not always be the case, Dr. Barrett says.
"There is increasing evidence that these lesions are not necessarily premalignant lesions. There is no question at all that patients with these lesions have an increased risk of developing melanoma. The data on that is very clear," he says. "Furthermore, the more lesions the patient has, the higher their risk of melanoma."
Because the dysplastic nevus lesion is a marker for a patient who is at increased risk, these patients need to get regular follow-ups from their dermatologist. "Patients will continue to develop new ones throughout their lifetime, and also the patients may develop melanoma. Dermatologists want to get that at as early a stage as possible, so that there is a better chance for a cure," Dr. Barrett says.
In addition to the initial biopsy and follow-up appointments, some dermatologists will re-excise the site, while others will not.
"Many dermatologists will no longer 'treat' the dysplastic nevus itself," Dr. Barrett says. "If they have biopsied them and it comes back as a dysplastic nevus, they won't re-excise them. There are other dermatologists who will re-excise all of them regardless of if they have positive margins on their biopsy, whether they have no atypia or whether they have severe atypia," he says.
Nationally, treatment practices vary from one practice to another. "I have seen a trend away from aggressive treatment and more into biopsy and follow-up, although there are a significant number of dermatologists who still re-excise these lesions," he says.
A study by Goodson AG, et al, published in the April 2010 issue of the Journal of the American Academy of Dermatology, evaluated the recurrence rates of previously biopsied dysplastic nevi. The study looked at patients with a history of a "nevus biopsy" at least two years earlier and assessed them for clinical recurrence. A total of 271 nevus biopsy sites were assessed in 115 patients.
The researchers found that in the cohort, rates of clinical recurrence after biopsy of dysplastic nevi and benign nevi were extremely low. Re-excision of nevi may not be necessary, they concluded.
The important message is that patients with these lesions should get regular dermatology exams, and dermatologists should follow them closely, Dr. Barrett says.
"The only controversy, really, is if you believe these are truly dysplastic and they will evolve - if left untreated - into melanoma, then you are going to re-excise them," he adds. "However, if you believe they are markers for patients who are at increased risk for melanoma, but that the lesions themselves don't necessarily evolve into melanoma, then follow-up with a patient is what you are going to do."