Thymoma

Experience with thymoma in 35 patients is reported. Seventeen had tumors that were malignant, and 18 had benign lesions. Cellular morphology was an unreliable index of malignancy. Seventeen patients had associated disorders: myasthenia gravis was present in 15 patients, hypoplastic anemia in 1 patient, and hypogammaglobulinemia in 1 patient.Treatment consisted of irradiation, resection, or a combination of both methods. Fifteen patients have died, 8 due to myasthenia, 4 due to tumor, and 3 from other causes. Sixteen patients are living and clinically free of tumor. Following treatment, remission of myasthenia occurred in 6 patients, but there was aggravation of the myasthenia in 2. In 4 patients myasthenia first appeared following treatment.In patients without myasthenia gravis, the prognosis is excellent for those with benign tumor and fair for those with malignant tumor. Myasthenia adversely affects the prognosis for both benign and malignant tumors. Resection is the treatment of choice for all operable thymomas, since the incidence of local malignancy is high and malignancy can only be determined at exploration. Preoperative irradiation may be useful in reducing the incidence of transpleural metastases.