CELLULAR FIBROUS DERMATOFIBROMA OF THE SOLE.

Cellular fibrous dermatofibroma is a rare variant of dermatofibroma/histiocytoma. We present a 61 years old female with a slow-growing, firm tumor on the sole of her right foot. The tumor was removed by slow Mohs surgery within 2 cm negative margin. Histopathologic investigation revealed a nodular encapsulated tumor composed of spindle and some epithelioid cells in a storiform growth pattern. Minimal mitotic activity was reported, however without evidence of atypical mitoses. Tumor cells expressed CD10, focally smooth muscle antigen and desmin, but remained negative for S100 protein and CD34. The diagnosis of cellular fibrous dermatofibroma was confirmed. The defect was closed by full thickness skin graft.