Late-Onset Nevus Comedonicus With Follicular Epidermolytic Hyperkeratosis-Case Report and Review of the Literature.

Nevus comedonicus is a rare cutaneous follicular hamartoma, characterized by the clustering of papules with firm, blackened horny buffers. It is usually present at birth or during childhood, although few cases of late-onset disease have been described. We present a case of postmenopausal-onset nevus comedonicus in a 55-year-old white woman without relevant medical history. Skin biopsy showed the typical features of several cyst-dilated follicular structures occupied by keratotic material and the peculiar finding of epidermolytic hyperkeratosis of the follicular epithelial walls. A brief review of the clinical and histological features of other similar cases published in the literature is performed.