A 9-year-old white girl presented with a rapidly growing pigmented papule, 6 × 5 mm, on her right leg (Figure 1A). Dermoscopy showed peripheral irregular streaks, a blue-whitish veil, and a central homogeneous yellowish hue (Figure 1B). The lesion was surgically removed. Histopathologic examination showed a dome-shaped compound spitzoid melanocytic proliferation extending into the dermis up to 1 mm in thickness (Figure 1C). Melanocytes were mostly arranged in confluent aggregates featuring a nodular dermal growth (Figure 1D). Mitotic rate was 2 mitoses/mm2. The histopathologic diagnosis was atypical spitzoid tumor (AST) with free margins. No further treatment was performed, and the patient was alive with no further evidence of disease at 10-year follow-up.
Simi L, Pinzani P, Salvianti F, Lorenzoni A, Tomasini C, Broganelli P, Orlando C, Pazzagli M, Massi D. Two Novel H-RAS Mutations Identified in a Child With an Atypical Spitzoid Tumor. Arch Dermatol. 2011;147(4):514-515. doi:10.1001/archdermatol.2011.76