Epithelial tumors of the thymus with pleural dissemination: the potential role of surgery

Background. Pleural metastases of thymic epithelial tumors are detected in 5-7 % of patients at initial diagnosis and in 10 % of patients during a follow-up after radical surgery for the primary tumor. Partial pleuroectomy is the cornerstone of treatment strategy in this group of patients. The aim of the study was to assess the role of surgery in the treatment of patients with thymic epithelial tumors with pleural dissemination. Material and Methods. From January1, 2010 to June 30, 2021, 21 patients with thymic epithelial tumors (thymoma - 13, thymic cancer - 8) and pleural implants (stage IVA - 11, isolated pleural metastases as tumor progression after radical surgery - 10) underwent partial pleuroectomy with resection of the diaphragm and lung if necessary. Four patients underwent inthraoperative photodynamic therapy and another 4 patients received intrapleural hyperthermic chemotherapy. Results. R0 resection was performed on 12 (57.2 %) patients. Postoperative complications were observed in 6 (28.6 %) patients. The mortality rate was 7.5 %. The overall 1-, 3- and 5-year survival rates were 78 % (95 % CI 61-95), 49 % (95 % CI 23-75), and 41 % (95 % CI 15-67), respectively. The median overall survival time was 29 months (95 % CI 0-60.6). Recurrence occurred in 10 (47.6 %) cases. One-year recurrence-free survival was 60 % (95 % CI 30-90). Independent negative predictors for overall survival were: thymic cancer, incomplete resection, presence of postoperative complications and local recurrence. Conclusion. Surgery is the mainstay of treatment for patients with pleural metastases (stage IVA thymomas and recurrent thymomas). Metastasectomy of pleural implants will be sufficient to achieve a complete resection.