Background: Cases of thymoma with pleural dissemination are occasionally encountered, and their management is difficult. Some reports have noted that surgical treatment for dissemination is effective, although the long-term results and clinical course details remain unclear. The current study investigated the short- and long-term outcomes of surgical resection of pleural dissemination.
Methods: A retrospective review examined the medical records for 38 patients who underwent surgical resection for pleural dissemination occurring synchronously with a primary thymoma or metachronously after complete surgical resection of a primary thymoma between 1996 and 2017 at the authors' institution. Clinical characteristics and prognostic factors were analyzed.
Results: The patients were classified into synchronous (n = 21) and metachronous (n = 17) groups. The 10-year overall survival rate was 59% for the synchronous group and 88% for the metachronous group. The median follow-up period for all the patients was 61 months (range 4-225 months). No perioperative deaths occurred. For all the patients, the 5- and 10-year overall survival rates were respectively 91% and 82%, and the 5- and 10-year relapse-free survival rates were respectively 29% and 19%. A significantly worse prognosis was observed for patients 50 years of age or older than for those younger than 50 years (p = 0.02). For 13 patients who underwent repeat resection for pleural dissemination, the prognosis was better than for those without repeat resection (p < 0.01).
Conclusion: Surgical resection of thymoma with pleural disseminated nodules can be safely performed and provides a favorable long-term outcome. Repeat resection is considered to be effective for achieving a good prognosis.