Multiple Dermatofibrosarcoma Protuberans Involving Head with Difficulty in Determining Surgical Margins for Resection: A Case Report

Abstract

　　Dermatofibrosarcoma protuberans（DFSP）is a rare, slow-growing fibro-cutaneous tumor of intermediate-grade malignancy that arises in the dermis of the trunk, proximal extremities, and, less commonly, in the head and neck area of adults. The high recurrence rate of DFSP, especially in the head, makes it particularly important to define tumor-encompassing margins for resection. However, due to the rarity of DFSP, clear guidelines for setting its resection margins are lacking, and for multiple DFSP involving the head, this is particularly challenging. Here, we describe a 22-year-old female presenting with multiple DFSP of the head. Due to a disparity between gross findings of the tumor and MRI data, the tumor was resected with a 20-mm margin from the Short T1 Inversion Recovery（STIR）high signal area on MRI, to minimize the risk of inadequate resection. Reconstruction was performed using a free latissimus dorsi flap. Postoperative pathology confirmed the negativity of the margins, and during the 8-month follow-up, there has been no evidence of recurrence or metastasis. This case report shows the potential utility of MRI STIR to determine safe excision margins in the presence of multiple DFSP, especially involving the head, where the risk of recurrence is high.