To the Editor.—
A young black man with xeroderma pigmentosum had a deeply pigmented nodular facial lesion of short duration. The overall histologic pattern of the growth was characteristic of a keratoacanthoma. In addition to the massive pseudoepitheliomatous hyperplasia, however, extensive proliferation of highly dendritic melanocytes was observed in all levels of the lesions.
Report of a Case.—
A 26-year-old black man with xeroderma pigmentosum was seen for an 0.8-cm deeply pigmented nodular lesion on the left cheek of three weeks' duration. The growth was elevated and showed smooth periphery and a central hyperkeratotic area. The patient is one of nine siblings with a younger brother and a sister who also have xeroderma pigmentosum. During a period of eight years, 12 other facial lesions were removed and were examined histologically. These included six squamous cell carcinomas and one actinic keratosis of lower lip, another actinic keratosis of the right cheek,
Mehregan A, Plotnick H. Pigmented Keratoacanthoma. Arch Dermatol. 1984;120(11):1417. doi:10.1001/archderm.1984.01650470023002