Myxoid malignant fibrous histiocytoma: experience with chemotherapy

Myxoid malignant fibrous histiocytoma (MFH) is an intermediate grade tumor with a definite metastatic potential but a relatively indolent natural history compared to the pleiomorphic variant of MFH. Little is known about its sensitivity to chemotherapy. We reviewed our experience with chemotherapy in myxoid MFH between 1986 and 1992. The patient population was identified through a search of the database maintained by the Departments of Melanoma-Sarcoma Medical Oncology and Pathology: 55 patients with histologically confirmed diagnosis of myxoid MFH were identified. Chemotherapy was administered to 18 of these patients (10 females, 8 males). The median age was 65 (range: 30-76). Ten patients had an extremity primary, seven had a trunk or retroperitoneal primary, and one patient had head and neck as the site of primary tumor. The median size of the primary tumor was 11 cm (range: 5-23 cm) in maximum dimension. Seven patients received chemotherapy in the neoadjuvant setting, eight received it for recurrent or metastatic disease, and three received it postoperatively after complete resection of the tumor. All patients received doxorubicin and dacarbazine with or without cyclophosphamide. Of the 15 patients evaluable for response, 4 achieved an objective response (one CR, 3 PRs, RR = 27%) to a median of 3 cycles (range: 1-7 cycles). At the time of last follow-up, eight patients are alive with no evidence of disease, two patients are alive with disease, and eight patients have expired. The median follow-up is 51 months (range: 26-216 months) from diagnosis. The relatively small sample precludes any definitive conclusions; however, it seems that doxorubicin- and dacarbazine-based chemotherapy has modest activity in myxoid MFH.