[The diagnostic value of the epidermal pigmentation in nevus-cell nevi (author's transl)].

The pigmentation of epidermis in areas of nevus-cell nevi is frequently not specially noted, but may be of considerable diagnostic value in particular cases. Two cases are demonstrated. Multiple tumors with the aspect of nevus Spitz in a 35-year old woman were histologically diagnosed by means of melanin impregnation methods as "amelanotic nevus-cell nevi with overlying vitiligo". A flat papillomatous nevus-cell nevus of the abdominal skin of a 38-year old man showed clinical signs of activity, but histologically only a total depigmentation of the epidermis and of the peripheral parts of the nevus was observed.