Dermatofibrosarcoma Protuberans with Fibrosarcomatous Areas: A Clinico-pathologic and Immunohistochemic Study in Four Cases

Abstract

Dermatofibrosarcoma protuberans (DFSP) with fibrosarcoma (FS)-like areas (DFSP-FS) is a peculiar neoplasm that combines microscopic findings of DFSP and FS. Because of the scarce number of cases published, tumor prognosis remains controversial. The clinical histories and the histologic material of 27 cases of DFSP were reviewed. Four of them showed fibrosarcomatous areas. Follow-up data, ranging from 12 to 125 months, were obtained in all four cases. Two patients had repeated local recurrences. One patient developed pulmonary metastases and died of disease 49 months after diagnosis. In the other two patients, no recurrences or metastases were detected at 12 and 70 months after local excision, respectively. Progressive increase of FS areas, cellular density, cellular atypia, and mitotic activity were observed during the recurrences. All cases showed diffuse positive immunostaining for CD34 in DFSP areas. Three cases were also CD34-positive in FS areas. Based on a careful review of the literature and our personal experience, we conclude that DFSP-FS is a rare variant of DFSP with a higher rate of local recurrences and more distant metastases than typical DFSP.

Low-grade Sarcomas with CD34-Positive Fibroblasts and Low-Grade Myofibroblastic Sarcomas

“…Fibrosarcoma can arise in DFS, both de novo and in recurrent lesions [9,[26][27][28][29][30][31]. It is characterized by greater cellularity with fascicular architecture and increased mitotic activity ( Figure 5).…”

Concomitant DNA copy number amplification at 17q and 22q in dermatofibrosarcoma protuberans

“…In some patients, the tumor also contains fibrosarcomatous components, or undergoes fibrosarcomatous transformation de novo or upon recurrence. Such transformation appears to carry an increased risk for recurrence and metastasis (Diaz-Cascajo et al, 1997;Mentzel et al, 1998). DFSP is characterized by strong CD34-immunopositivity, whereas fibrosarcomatously transformed areas of the tumors express CD34 less consistently (Sato et al, 1995).…”

Aspiration Cytology of Fibrosarcomatous Variant of Dermatofibrosarcoma Protuberans with Osteoclastlike Giant Cells in the Chest Wall

“…Primary and recurrent DFSP can progress to FS-DFSP, which can metastasize and be fatal. [3][4][5] Although DFSP can occur at any site, the most common …”

“…2 Rarely, does DFSP have areas indistinguishable from conventional fibrosarcoma; such areas occur de novo or in a recurrence. [3][4][5] Although the histopathology of this tumor and its variants has been well described, 2 series 6,7 and a few reports 5,8,9 have characterized the cytologic features of DFSP, and only 1 review 6 has described the cytologic findings of the fibrosarcomatous variant of DFSP (FS-DFSP). To the best of our knowledge, osteoclastlike giant cells have not been described in any cytologic report of FS-DFSP or DFSP.…”