A case of myxofibrosarcoma of the maxilla with difficulty in preoperative diagnosis.

Myxofibrosarcoma (MFS) is a very rare fibroblast-derived sarcoma that occurs in the head and neck region. Here, we report the case of a 52-year-old man in whom MFS generated from the maxilla and whose beginning of treatment was considerably delayed because he was initially diagnosed as having a benign inflammatory lesion. Because a definite diagnosis was not obtained via 2 independent biopsies, total maxillectomy was used for both diagnosis and treatment. Histopathological and immunohistochemical analyses suggested that the tumor was a low-grade MFS. Because soft tissue tumors in the head and neck region are rare and a definite diagnosis is relatively difficult, surgical excision is indispensable if malignancy of the tumor is suspected.