Blue Nevus. Presented by Laurence J. Underwood, MD, and Walter S. Green, MD.
A six-year-old Mexican-American boy had a blue-black lesion on the dorsum of his foot since birth. His mother stated that it had grown in diameter and in thickness. Small satellite lesions developed near it.The lesion was a firm, elevated, blueblack, round tumor measuring 1 cm. Adjacent to it were several macules and papules of similar color, measuring a few millimeters in size. A small tan macule was noted in the right sacral area.A punch biopsy is presented.
Discussion
Dr. Paul Hirsch: The clinical appearance of the pigmented tumor is more disconcerting than the microscopic. A densely pigmented tumor of fusiform mononucleated cells, diffusely distributed throughout the dermis and intimately related to a fibrous connective tissue stroma, is separated from the epidermis by a thin zone. The melanin pigment throughout the nevus is pronounced and occludes