Malignant fibrous histiocytomas of the head and neck.

Fibrous histiocytomas are soft tissue neoplasms of histiocytic origin showing partial fibroblastic and histiocytic differentiation. The histopathology of these tumors and their nomenclature are discussed. A case of primary intraosseous malignant fibrous histiocytoma of the mandible is presented and added to the previously reported nine cases. One hundred and ten cases of fibrous histiocytoma are reviewed, a rapidly increasing number of reported cases in the deep tissues of the head and neck region. No definite reliable histologic criteria have been found to predict the true malignant lesions. Malignant fibrous histiocytomas show the most aggressive behavior in the head and neck region with a metastatic rate of 30-42%. Aggressive surgery remains the treatment of choice with a five year survival rate of approximately 60%, chemotherapy and radiotherapy being used as adjunctive treatment.