2001 Volume 111 Issue 7 Pages 1105-1109
A 56-year-old male presented with a subcutaneous tumor (6×6.5×3.5 cm) on the lumber area of about 8 years duarations. The tumor was elastic hard and showed no adherence to the underlying muscles in the CT scan examination. The whole tumor was excised with a 3 cm surgical margin. On histologic evaluation, the tumor was consisted of areas of ordinary dermatofibrosarcoma protuberans (DFSP) composed of uniform spindle-shaped tumor cells with storiform or cart-wheel growth patterns. In other histologic areas, a dense proliferation of atypical spindle cells arranged in fascicular and herring-bone patterns was also observed. Immunohistochemical staining for CD34 was negative in fibrosarcomatous areas (DFSP-FS) but positive in DFSP areas.