Penile melanosis.

Five patients with penile melanosis are described. The lesions consisted of macular hyperpigmentation of the penile shaft and/or glans. Histologically only hyperpigmentation of the basal cell layer was observed with no melanocytic hyperplasia. Patients had follow-up for 3 to 13 years; enlargement of some lesions was observed, but the condition remained benign. The main differential diagnostic problem was with acral lentiginous melanoma. Penile melanosis shares clinical and microscopic features with Laugier-Hunziker syndrome of the buccal mucosa and vulvovaginal melanosis. We suggest that the three disorders be grouped as essential melanotic hyperpigmentation of mucosa.