A Fibrosarcomatous ("High-Grade") Variant of Dermatofibrosarcoma Protuberans (DFSP

Abstract

Dermatofibrosarcoma protuberans (DFSP) is a relatively uncommon soft tissue tumor with intermediate-to-low grade malignancy. There is usually little nuclear pleomorfism and only low to moderate mitotic activity. Conventional DFSP, usually have fewer than 5 mitotic figures/10 high-power fields. We describe a case of a 74-year old male patient who presented to the surgical clinic with active bleeding from a painless mass in his right arm which has grown progressively over a period of two years. Local excision of the mass was performed. Histopathological evaluation showed dermatofibrosarcoma protuberans with high mitotic activity (15 mitotic figures/10 high-power fields and high nuclear pleomorphism. Therefore, it was diagnosed as a fibrosarcomatous (high grade) variant of dermatofibrosarcoma protuberans (FS-DFSP). Only 225 cases of DFSP-FS being described in the literature, thus, the importance of this case report arises due to the rarity of this clinical and histopathologic entity.