Malignant thymoma: role of radiation therapy in management.

Malignant thymoma is a rare tumor generally seen as an anterior mediastinal mass. Radiation therapy in ten patients with malignant thymoma diagnosed in 1968-1983 was reviewed retrospectively. Surgical therapy consisted of subtotal resection in four patients and biopsy only in six. Megavoltage irradiation in the dose range of 4,600-5,250 cGy was employed. In all symptomatic patients, palliation of presenting symptoms was achieved. In seven patients, a greater than 50% reduction in tumor mass followed radiation therapy. Local control was achieved in six patients. Three patients show no evidence of disease clinically, after a minimum follow-up study of 1 year. Radiation therapy is an important therapeutic modality in the control of malignant thymoma.