2018 年 24 巻 1 号 p. 6-12
Purpose: To analyze the role of surgery in patients with Masaoka stage IVa thymoma treated with multimodality therapy.
Methods: Of 191 patients undergoing surgery for thymoma in our department between January 2002 and December 2015, 39 (20.4%) had Masaoka stage IVa. Histopathological tumor type, myasthenic status of the Osserman–Genkins score, Masaoka stage at the first surgery, neoadjuvant treatment, number and type of surgeries, and survival rates were recorded.
Results: Thymoma B2 was the most common histopathological tumor type (n = 16, 41%). Twenty-six (66.7%) patients underwent primary surgeries for Masaoka stage IVa thymoma, whereas nine (23.1%) underwent secondary surgeries and four (10.3%) underwent tertiary surgeries for pleural or pericardial recurrences. Median survival was 132 ± 25 (82–181; 95% confidence interval [CI]) months. Overall 3-, 5-, and 10-year survival rates were 93%, 93%, and 56%, respectively.
Conclusion: Surgical treatment should be considered as a completion modality to oncological therapy and has the potential to provide long-term survival of Masaoka stage IVa in patients with thymoma. The type of surgery should be determined based on the invasiveness of the lesion.