Histologic outcomes of excised moderate and severe dysplastic nevi.

Background: Dysplastic nevi (DN) have been a matter of controversy since their initial description in 1978 because of differences in the clinical and histological terminology, and large studies on histological outcomes of excising moderate to severely DN have not previously been described.

Objective: To determine the clinical characteristics of DN and histologic outcomes of excised moderate and severe DN.

Methods: Retrospective chart review of patients with DN or Clark's nevi at the Dermatology Department at Rutgers-Robert Wood Johnson Medical School in Somerset, New Jersey, from January 2009 to June 2012. Three hundred ninety-three lesions from 380 patients were included in this study.

Main Outcome Measure: Histologic results of excised moderate and severe DN.

Results: Thirty-four percent of DN were excised because of the presence of moderate or severe atypia, personal history of melanoma, or both. None of the excised lesions showed evidence of melanoma; 81.6% of excisions showed scar or granulation tissue. Only 14% of excised lesions were found to have residual lesions, and 4.4% showed recurrent nevi.

Conclusion: In 134 excisions of moderate to severe DN, no melanoma was identified. Most of the excisions showed scar or granulation tissue. The rate of residual lesions after shave biopsy of moderate or severe DN was lower than after punch biopsy.