Intraoral Spitz nevus: case report and literature review.

Spitz nevi account for approximately 1% of all melanocytic nevi of the skin in children. Although Spitz nevi often develop in the skin of the head and neck, intraoral Spitz nevi are rare. These nevi contain epithelioid and spindle cells and exhibit cytologic and architectural atypia when compared with routine melanocytic nevi, and may be mistaken for atypical Spitz tumor, Spitzoid melanoma, or conventional melanoma. Here, we report a Spitz nevus on the buccal mucosa of an 11-year-old boy. The tumor was composed of a proliferation of mostly epithelioid melanocytes with a smaller spindle cell component. The melanocytes were positive for S100, MART-1, and p16 proteins, with HMB-45-positive cells located only in the basal cell layer and superficial lamina propria. Less than 5% of the nuclei were positive for MIB-1, and there were no mitotic figures. We review the literature on 7 previously reported cases of Spitz nevi.