A rare aggressive skin tumor that develops in the skin. The tumor consists of melanin-producing cells which increases the skins pigmentation in the affected area. Metastasis is rare but it often regrows after being surgically removed. It occurs mostly on the trunk, shoulders and chest.
* Painless skin lump * Firm skin nodule * Red-brown skin lump * Asymptomatic * Red-blue skin lump
The differential diagnosis with (non-pigmented) dermatofibrosarcoma protuberans is based on the presence of this population of pigmented cells. Two cases of pigmented dermatofibrosarcoma protuberans (Bednar's tumor) are reported here in, and a discussion follows on the clinicopathological features of this neoplasm and the different hypotheses on its histogenesis.
Several studies reveal an almost equal sexual distribution or a slight male predominance. In a large study3 of 902 patients with DFSP conducted by Rutgers et al, 514 (57%) patients were male and 388 (43%) patients were female. DFSP usually occurs in adults aged 20-50 years. Rarely, DFSP has been reported in newborns and elderly individuals (80 y).