Myxofibrosarcoma of unusual sites

Myxofibrosarcoma classically presents as a painless mass in the proximal extremities. Cutaneous myxofibrosarcomas arising in the head and neck and distal extremities are extremely uncommon. We present a series of 6 cases of myxofibrosarcoma presenting in the head and neck and acral locations.Archives were searched using the term "myxofibrosarcoma" over a 6-year period (2009-2015). The clinicopathologic features of myxofibrosarcoma were recorded. Cases in the head and neck or acral locations were retrieved. When available, the patient's medical records were reviewed.Ninety-five cases of myxofibrosarcoma were identified over a 6-year period. Six patients were identified with myxofibrosarcoma arising in the head (n = 4, M:F 3:1), hand (n = 1, F) and foot (n = 1, F). Each had typical features of myxofibrosarcoma. Two of the tumors on the head were high-grade and had multiple recurrences, while the remaining 2 were intermediate grade. Both acral tumors were intermediate grade and 1 recurred locally within a year of diagnosis.Myxofibrosarcoma may rarely involve the head and neck and acral locations, and presentation in these sites is a potential source of diagnostic difficulty. Recognition of the characteristic histologic features of myxofibrosarcoma in conjunction with judicial use of immunohistochemical stains should allow for accurate diagnosis.