Thymoma with dissemination: efficacy of macroscopic total resection of disseminated nodules.

BACKGROUND: Advanced thymomas with disseminated nodules are difficult to manage, and the treatment strategy remains undefined.
METHODS: A total of 28 thymoma patients with pleural and/or pericardial disseminated nodules were treated at Nagoya City University Hospital. Among them, 21 patients underwent resection of thymoma and pleural disseminated nodules. These patients were reviewed in the present study.
RESULTS: Preoperative steroid pulse therapy was performed in 14 patients. Macroscopic total resection of all tumors was achieved in 15 patients. Postoperative adjuvant radiotherapy was performed for the mediastinum in 20 patients and hemithoracic irradiation (HTR) in 11 patients. The overall survival rate of operated 21 patients was 73.1% at 5 years. The patients who underwent resection showed a better prognosis than the patients without resection (p = 0.0006). Relapse was diagnosed in 14 of 21 patients who underwent resection. Disease-free survival was 67.5% at 1 year, 39.8% at 3 years, and 13.3% at 5 years. HTR alone did not improve the disease-free survival. Among the patients who underwent total resection, relapse-free survival was better than in the patients with subtotal resection (p = 0.009). Achievement of a trimodality therapy with preoperative steroid pulse, total resection, and postoperative HTR was associated with prolonged relapse-free survival in the operated patients (p = 0.027, hazard ratio 6.452).
CONCLUSIONS: Pursuing total resection for thymoma and disseminated nodules may be beneficial for stage IV thymoma. The combination of preoperative steroid pulse therapy, macroscopic total resection, and postoperative HTR may prolong the interval to relapse, but it did not lead to cure.