Assessing the Need for Re-Excision in Mild to Moderate Dysplastic Nevi

The procedures we follow for managing dysplastic nevi are relatively straightforward, and yet a variety of factors should be weighed when deciding on a particular course of action. Excision is not only costly, but can be uncomfortable for patients, particularly in the post-procedure healing period. It is difficult to determine with certainty when we should perform excision. Given the risk of melanoma, physicians should carefully weigh all options.

Clarifying the uncertainties regarding the treatment of dysplastic nevi, a new study published in the Journal of the American Academy of Dermatology examines various decision points of treatment, particularly efficacy rates of re-excision against the cost of the procedure.¹

THE UTILITY OF RE-EXCISION

The authors of the study work from the basis of the controversy surrounding the management of dysplastic nevi: “Clinicians agree that margin-positive severely DN should be removed with a surgical margin, however, there is disagreement surrounding the appropriate management of margin-positive mildly and moderately DN.”

Seeking to evaluate the utility of re-excising margin-positive mildly and moderately DN, they conducted a retrospective chart review on all adult patients given the diagnosis of a biopsy- proven DN from 2010 through 2011. They defined primary outcomes as the presence of melanocytic residuum in re-excisional specimens and a clinically significant change in diagnosis.

Of the total 1,809 diagnoses of mild to moderate dysplastic nevi from 2010 through 2011, 765 (42.3 percent) were found to have positive surgical margins during biopsy. Additionally, 495 (64.7 percent) of the 765 lesions were subsequently re-excised. Melanocytic residuum was present in 18.2 percent of re-excisional specimens and in only one case re-excision resulted in a clinically significant alteration of the diagnosis.

Given the low rate of dysplastic nevi transforming to melanoma, coupled with the low rate of residual melanocytic lesions on re-excision and even lower rate of a re-excision altering the diagnosis, the authors conclude that re-excision of these nevi rarely results in a clinically significant change in diagnosis. Moreover, they suggest that the practice of clinical monitoring of margin-positive lesions, in addition to being safer and costefficient, may also be clinically appropriate.

CONCLUSION

The controversy surrounding dysplastic nevi will persist. Depending on the comfort level of the pathologist, many will still excise moderate dysplastic nevi-particularly in view of increasing restrictions of exactly who reads our pathologic specimens due to insurance regulations and obvious cost cutting maneuvers by the large insurance “players” of our time. Obviously all must err on the side of being conservative, thus it is hard to argue against this rationale. However, if a clinician is comfortable with their pathologist, and there is agreement on the definition of a moderate dysplastic lesion being very distinct from severe atypia, then certainly observation of margin positive atypical nevi is a clinical option. Further, many dermatopathologists will firmly suggest re-excision on such borderline lesions and clinicians must step aside to these suggestions and move ahead with a second procedure. A team approach to the problem serves all interests and most importantly, is in the best interest of our common goal: high quality patient care.

Jonathan Wolfe, MD is a Clinical Associate Professor of Dermatology, University of Pennsylvania, where he is on the staff of the Pigmented Lesion Clinic. He is also Division Head of Dermatology, Einstein Montgomery Hospital, East Norriton, PA.

1. L Strazzula, P Vedak, MP Hoang, A Sober, H Tsao, D Kroshinsky. The Utility of Re-Excising Mildly and Moderately Dysplastic Nevi: A Retrospective Analysis. J Am Acad Dermatol 2014 Sep 25.