Dermatofibrosarcoma Protuberans: The Current State of Multidisciplinary Management.

Dermatofibrosarcoma protuberans (DFSP) is a rare, infiltrative, soft tissue tumor. It has a propensity for deep invasion but a low risk for distant metastasis. The classic presentation is a slowly progressive, painless, and erythematous to purpuric patch on the trunk or arms. A deep, subcutaneous punch biopsy or incisional biopsy should be performed for diagnosis in all suspected cases; wide undermining of the skin is to be avoided for minimizing the risk of tumor seeding and for retaining the feasibility of histopathologic examination of re-excisions. Histopathologic distinction of DFSP from dermatofibroma requires immunohistochemical assessment for CD34, factor XIIIa, nestin, apolipoprotein D, and cathepsin K. Management of this cutaneous sarcoma involves a multidisciplinary oncologic approach. Surgical excision is usually the first step in management. DFSP has a high propensity for local recurrence, even when surgical margins are negative; therefore, radiation therapy or rarely systemic therapy is recommended, especially for locally advanced or metastatic cases. The indolent nature of DFSP requires lifelong surveillance for recurrence; however, most recurrences occur within 3 years of the primary excision. The median time for the development of a local recurrence is estimated to be 32 months. An emerging theragnostic transmembrane receptor target, folate hydrolase-1 (FOLH1; prostate-specific membrane antigen), has been expressed in benign dermatofibromas and in high-grade sarcomatous phenotypes. These findings suggest that DFSP may also express FOLH1, which could allow for surveillance with FOLH1 PET/CT and antibody-mediated brachytherapy.