[Thymoma--report of 268 cases].

This paper reports 268 cases of thymoma treated by surgery and followed up to 24 years in our hospital. We believe that thymoma is a low grade malignancy. The gross findings on thoracotomy and microscopic examination are useful for diagnosis. The prognosis is related to the morphology of the tumor capsule. For patients with noninvasive thymoma, the prognosis is excellent and the recurrence rate is the lowest. In spite of a benign histologic feature, the prognosis is poor for patients with invasive thymoma which gave a 5 and 10 year survival rate of 65.5% and 48.8%, respectively with a recrudescence rate of 41.0%. Surgery is strongly indicated for thymomas. Invasive thymoma must be excised as early as possible. Extensive and thorough resection is the best way of preventing recurrence. The recurrent or metastatic foci can also be resected and cured by surgery. The survival time may be prolonged by radiotherapy. The residual tumor tissue can be effectively controlled by postoperative irradiation. The recurrent tumor may also be cured by radiation. Yet the result of patients with intrapleural seeding is not improved by postoperative radiation.