REOPERATION FOR THYMOMA - REPORT OF 23 CASES

Twenty-three patients underwent reoperation for thymoma at intervals of 2 months to 17 years 10 months after the initial operation. There were no operative or hospital deaths. Myasthenia gravis occurred in 12 patients, but in only 2 was it a determinant for reoperation. The longest survival after reoperation is 12 years 9 months, and that patient is free from tumor. Four distinct surgical groups emerged, and their recognition provides an improved method of reporting and suggests a strategy for better overall management. Group 1 (n = 5) had completion of thymectomy (reoperation) after thymomectomy alone or after incomplete thymectomy. The interval was 2 months to 17 years 10 months. All 5 had myasthenia gravis. At reoperation, thymomas were found in 3 and a hyperplastic thymus in 2. Four are alive and tumor free 2 years to 8 years 2 months after reopetation. One died tumor free after 5 years. Group 2 (n = 8) had reoperation for recurrent thymoma after standard (presumably complete) resection. The interval was 2 years to 13 1 2 years. Four had myasthenia gravis. Four are alive 8 months to 5 years 8 months after reoperation, 3 without detectable tumor. Four died 3 years 3 months to 8 years 4 months after reoperation, 3 free from tumor. Group 3 (n = 8) underwent reoperation for initially unresectable thymoma after adjuvant treatment with chemotherapy, radiotherapy, or both. The interval was 3 months to 4 years 8 months. Three had myasthenia gravis. Six are alive 4 months to 4 years after reoperation, only 1 with tumor. Two died 1 year 5 months and 6 1 2 years after reoperation, both with tumor. Group 4 (n = 2) underwent reoperation for miscellaneous reasons. The interval was 2 months and 3 1 2 years. Neither had myasthenia gravis. One had thymoma at reoperation and is alive, tumor free, 12 years 9 months postoperatively. The other, reoperated on for a mediastinal mass at 3 1 2 years, had metastatic breast cancer, not thymoma. Reoperation for thymoma can be followed by prolonged tumor-free survival. Thymomectomy alone or incomplete thymectomy should be abandoned. Recurrent thymoma is most often limited to the thorax, thus facilitating reoperation. The response of initially inoperable thymoma to adjuvant therapy favors subsequent reoperation. Slow growth and late appearance of recurrence necessitate lifelong follow-up. Myasthenia gravis, when present, had no deleterious effect on operation. © 1990.