Incidental epidermolytic hyperkeratosis and focal acantholytic dyskeratosis in common acquired melanocytic nevi and atypical melanocytic lesions.

Abstract

Epidermolytic hyperkeratosis (EH) and focal acantholytic dyskeratosis (FAD) are distinct histologic patterns that have been observed incidentally in a variety of benign and malignant skin lesions, including melanocytic lesions. Our motivation for this study was to determine whether FAD and/or EH was significantly associated with atypical melanocytic lesions. Skin biopsy specimens of melanocytic lesions diagnosed at our facility over a 3-month period were examined for the occurrence of FAD and EH. Whereas both FAD and EH are uncommon findings, FAD was statistically increased in atypical melanocytic lesions (P =.0172). EH was not found to differ significantly in common acquired melanocytic nevi vs atypical melanocytic lesions. Although both can be found in association with nonneoplastic skin diseases, as well as cutaneous neoplasms, FAD, but not EH, might serve as a marker for melanocytic atypia. Taken together with findings in the literature, FAD might serve as marker for atypical cutaneous proliferations as a whole.