Long-Term Outcomes After Surgical Resection for Pleural Dissemination of Thymoma

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