Two Cases of Dermatofibrosarcoma Protuberans With Fibrosarcomatous Change

Abstract

Herein, we describe two cases of dermatobrosarcoma protuberans with brosarcomatous change : Case 1 : A 36-year-old man presented with a subcutaneous mass in the right rib area, which had gradually increased in size. He recalled a history of trauma to the same area from being struck by disposable chopsticks several years prior. Upon examination and after skin biopsy, the mass was diagnosed as dermatobrosarcoma protuberans (DFSP). An extended excision with a 3 cm margin was performed to remove the tumor. Case 2 : A 40-year-old man noticed a subcutaneous mass on his lower abdomen two months prior. He underwent a total excisional biopsy at the rstvisit. In both cases, the tumors consisted of spindle-shaped tumor cells with storiform pattern. In some areas, there was a dense proliferation of atypical spindle cells arranged in fascicular and herringbone patterns with mitotic gures. Immunohistochemical staining revealed decreased expression of CD34 in the brosarcomatous area. We diagnosed both patients as DFSP with brosarcomatous change (DFSP-FS). DFSP is a relatively rare soft tissue tumor that is considered to be intermediate malignancy. It frequently recurs locally ; however, systemic metastases are rare. DFSP-FS is more likely to metastasize than normal DFSP. In both the present cases, no local recurrence and metastases were observed over 3 years post-operation. It is necessary to perform careful long-term follow-up for the management of DFSP-FS Skin Research, 23 : 201-205, 2024