Epidermolytic hyperkeratosis associated with melanocytic nevi: a report of 53 cases.

Epidermolytic hyperkeratosis (EH) is a unique histopathologic alteration of the skin characterized by hyperkeratosis with perinuclear vacuolization of keratinocytes primarily in the stratum granulosum and the stratum malpighii. It is seen as an incidental finding in a variety of conditions, benign and malignant, as well as sporadic and familial. Recently, it has been reported that EH may be associated with dysplastic nevi (nevus with architectural disorder [NAD]). Cases of melanocytic nevi with epidermolytic hyperkeratosis were retrieved from the files of a referral dermatopathology laboratory over a 6-year period. We present a series of 53 cases of EH in both ordinary nevi and NAD. Epidermolytic hyperkeratosis identified in association with NAD accounted for 46 cases or 86.8% of the total lesions while ordinary nevi represented 7 or 13.2% of total cases. Our study confirms that the incidence of EH is higher in association with dysplastic nevi than in ordinary melanocytic nevi and may serve as a marker for NAD, but with lower sensitivity and only moderate specificity.