Thymoma: clinicopathologic features, therapy, and prognosis.

We have treated 40 patients with thymoma. All the 18 with benign thymoma were treated with resection alone and none had a tumor recurrence or died from disease-related causes. Postoperative survival in this group ranged from 2 months to 14 years. Of the 22 patients with malignant thymoma, 2 underwent total resection, 10 partial resection and 10 were non-resectable. Fifteen of the 20 patients with non-resectable and partially excised thymomas were given radiotherapy. The cumulative 5- and 10-year survival rate of irradiation treated patients was 45.6%, and 34.4%, respectively. Of 6 non-irradiated patients, only one who underwent complete excision of tumors survived for more than 10 years, and 5 died within 3 years after treatment. Based on our findings we suggest that all patients with malignant thymoma, irrespective of the extent of surgical treatment, should be given postoperative irradiation.