Giant dermatofibrosarcoma protuberans in the forearm

Dermatofibrosarcoma protuberans (DFSP) is a rare, slow-growing, locally aggressive malignant fibroblastic mesenchymal skin tumor, which is considered as the most common skin sarcoma. As a treatment modality, local excision with 4-5 cm border is commonly replaced by Mohs micrographic surgery. A 24-year-old woman with a giant DFSP in the forearm is presented. The patient was admitted to clinic with a large protuberant mass on the left forearm. The preliminary diagnosis was soft-tissue sarcoma due to a history of rapid growth and absence of any skin lesion. DFSP originates from the dermis and commonly infiltrates underlying muscles, tendons, fascia, and bones. In this case, there was no skin infiltration. Mohs micrographic surgery was not used in the treatment since the tumor was confined to subcutaneous tissue and did not infiltrate to the skin. Although the Mohs micrographic surgery was not used, the tumor did not recur postoperative 6 months' follow-up. A long-term follow-up is strongly recommended in DFSP cases.