Dermatofibrosarcoma Protuberans, often abbreviated DFSP is a slow growing, non-painful tumour. It is sometimes preceded by antecedent trauma in ten to twenty percent of cases and typically presents in the age group of young adults. The tumour is more common amongst males than females and is distributed on the trunk, groin, and proximal extremities, which distinguishes it from dermatofibroma, as the aforementioned tumour occurs on the distal extremities.
Dermatofibrosarcoma Protuberans presents grossly as a solitary mass of the subcutis and skin, averaging five centimetres in size. The tumour may lead to the ulceration of overlying skin with associated hemorrhage and cystic change.
In immunohistochemistry, Dermatofibrosarcoma Protuberans is CD34 positive. In cytogenetics, there is a supernumerary ring structure formed by amplified sequences of chromosomes 17 and 22. There is also fusion of COL1A1 and PDGFβ genes; as such, overexpression of PDGFβ may lead to DFSP.
DFSP is locally aggressive and recurs in fifty percent of all cases. However, it rarely metastasize (<4% of cases). The treatment for the tumour is wide surgical excision; radiation therapy is used for large tumours or positive margins.