Perianal Pigmented Variant of Dermatofibrosarcoma Protuberans

Dermatofibrosarcoma protuberans (DFSP) is a low-to-intermediate grade cutaneous sarcoma with reported at 3 per 1,000,000 individuals. It is a locally aggressive tumor which originates in the dermis and invades deeper structures. Up to 90% of cases of DFSP are associated with a translocation between chromosomes 17 and 22. These tumors have a high risk of local recurrence but very rarely exhibit metastatic spread. Several histologic variants exist, including fibrosarcomatous DFSP, and in this case, pigmented DSFP. Pigmented dermatofibrosarcoma protuberans, otherwise also known as a Bednar tumor, is a rare variant of DFSP first described in 1956 which accounts for less than 5% of all DSFP cases. It is distinguished by the presence of melanin containing dendritic cells within the tumor. Histologically, tumor cells are arranged in compact spindle shaped bundles. These tumors may be derived from neuroectodermal cells although no consensus has been reached. DSFP occurs equally in men and women and most commonly occurs in young to middle aged adults. These cutaneous sarcomas typically present on the trunk, back and shoulders as a slow-growing mass or plaque that may be hyperpigmented. Less that 1% present on genitalia, and only two DSFP cases to date have been reported involving the perianal region.https://scholarlycommons.henryford.com/merf2019caserpt/1085/thumbnail.jp