LAUSR

Subcutaneous dermatofibrosarcoma protuberans (SC-DFSP) was recently characterized as an uncommon subtype of DFSP. It was initially described by Diaz-Cascajo in 1998 as “deep DFSP.” It appears as a poorly circumscribed tumor or nodule that involves subcutaneous tissue but lacks the visible nodular surface of classic-DFSP. SC-DFSP occurs more commonly on the head and neck and may extend significantly beyond the palpable clinical lesion. Compared to classic DFSP, SC-DFSP requires a greater number of Mohs stages to clear margins and is more likely to extend to deeper structures such as the muscle or periosteum. Therefore, there is a high-risk for large surgical defects, necessity for complex reconstruction, and cosmetic deformity or functional impairment in the head and neck region. Oral tyrosine kinase inhibitor imatinib has been successfully used to treat unresectable or metastatic classic-DFSP and DFSP with fibrosarcomatous change. We present a case of locally advanced SC-DFSP on the head and neck that demonstrated clinical and radiographical response to therapy with imatinib. A 33-year-old female was referred for evaluation of an indurated lesion on the left face. On physical exam, there was an ill-defined 7.0