Dermatofibrosarcoma protuberans (DFSP) is a rare, slow-growing soft tissue tumor accounting for less than 0.1% of all malignant neoplasms and approximately 1% of all soft tissue sarcomas.
We report a case of a 27-year-old female who presented with a 1-year history of a gradually enlarging firm, erythematous to violaceous nodule on the right anterolateral leg. Shave excision biopsy was done, and revealed spindle-shaped fibroblasts arranged in a storiform pattern around an indistinct vasculature. Histopathologic diagnosis revealed dermatofibrosarcoma protuberans. There was prominent, diffuse, positivity for CD34 by immunohistochemistry. The cytogenetic analysis revealed a t(17;22) translocation, confirming our working impression.The patient underwent wide excision with frozen section. All surgical margins of resection were negative for tumor. The patient was referred to plastic surgery for post-excision coverage defect. Split-thickness skin graft was applied over the defect. Patient tolerated the procedure well, and has not experienced recurrence of the tumor.
A protuberant, well-circumscribed tumor that seems benign may incidentally be a sarcoma. Skin biopsy, immunohistochemistry and cytogenetic studies using Fluorescence In-Situ Hybridization (FISH) are the most essential laboratory investigations to validate a diagnosis of DFSP. Proper surgical excision with adequate margins will prevent recurrence of the tumor.