[A case of thymoma with pleural dissemination which was treated by pleurectomy with patient survival without recurrence for more than five years].

A 46-year-old woman was admitted to our hospital with chest pain. Chest X-ray and CT revealed an anterior mediastinal mass as well as several small masses attached to the left chest wall. Thymoma was diagnosed by percutaneous biopsy. The serum level of anti-acetylcholine receptor antibody was 30.3 pmol/ml. At operation, the thymoma was found left in the anterior mediastinum, extending to the upper lobe of the lung. There were also numerous tumors of various size in the left parietal pleura. Thymectomy, partial resection of the upper lobe of the lung and pleurectomy were performed. One month later, she developed myasthenia gravis. After a complete remission of myasthenia gravis brought about by anti-choline esterase therapy, the patient was treated with irradiation. She has been well for more than five years after the operation but her serum anti-acetylcholine receptor antibody level is still higher than normal.