A morphologic study of dermatofibrosarcoma protuberans: expansion of a histologic profile

Dermatofibrosarcoma protuberans (DFSP) is a fibrohistiocytic tumor of inter mediate malignancy characterized by a distinctive storiform growth pattern and frequent local recurrences. In this study, we retro-spectively reviewed 48 cases of DFSP diagnosed at the Cleveland Clinic Foundation between 1970 and 1999 to determine the prevalence of morphologic variations including t he presence of giant cell fibroblastoma (GCF)-like areas, multinucleated gi ant cells, hypercellular zones and fibrosarcomatous change. Results: The co hort consisted of 42 patients (20 males, 22 females) with a median age at d iagnosis of 40 years (range: 10-73 years). Forty-one primary tumors and sev en recurrences were evaluated from these 42 patients. Tumor sites included the trunk (22 cases), head and neck (8 cases), upper extremities (7 cases) and lower extremities (6 cases). GCF-like area were identified in seven (14 .6%), multinucleated giant cells in ten (20.8%), hypercellular zones in 12 (25%) and fibrosarcomatous change in six (12.5%) cases, respectively. Combi nations included giant cells and GCF-like areas (Two cases), giant cells an d hypercellular zone (two cases), and GCF-like areas and hypercellular zone s (one case). Our findings suggest that DFSP has a wider range of morpholog ic features, including GCF-like areas, multinucleated giant cells, hypercel lular zones and fibrosarcomatous change, than has been previously recognize d in the literature.