Pigmented storiform neurofibroma.

A case of pigmented storiform neurofibroma is presented. The lesion was present in the right loin of a 35-year-old Japanese woman. Grossly, a round, slightly elevated, approximately 1.5 cm in diameter tumor showed a red-purplish coloration of the central part of the overlying skin without ulceration. The characteristic storiform pattern and scattered melanin-containing cells were the relevant features for histological diagnosis. To our knowledge, our case is the second reported case in Japan. The histogenesis and its relationship with tumors of neural crest origin is briefly discussed.