Radiation-induced malignant fibrous histiocytoma: a report of five cases including two occurring post whole brain irradiation.

Five patients who were successfully treated with external radiation therapy for a variety of histologically unrelated tumors subsequently developed malignant fibrous histiocytoma (MFH) within the irradiated field. It is suggested that therapeutic irradiation was a causative factor in the development of these tumors with latent periods ranging between 3 and 17 years. A review of the pertinent literature is presented. It is apparent that postradiation MFH is being recognized with increasing frequency and at an earlier age than when it appears de novo.