Thymomas are rare human tumors characterized by a variety of histological types, clinical manifestations and an unpredictable prognosis. The experience that has been accumulated with the diagnosis and treatment of thymomas even in the leading specialized thoracic clinics during a few decades is little with one to several hundred cases. Accordingly to date, there is no consensus on various issues of treatment for this disease, including the treatment policy for recurrent thymomas, by using a surgical technique. The paper describes the case of a 48-year-old female patient who underwent combined treatment (thymomectomy and resections of the right pericardium, mediastinal pleura, lung, and phrenic nerve with additional postoperative radiation therapy) for locally advanced thymoma more than 10 years ago. The patient was regularly examined after treatment, with the result that thymoma recurrences that were always located in different parts of the right parietal, mediastinal, and visceral pleura were found 46, 84, 96, 109, and 116 months after treatment for primary tumor. The detected recurrent thymomas were surgically removed at the same time; the histological type of type B1 thymoma was seen in all cases. After 10 years and 9 months of treatment, the patient is alive without the clinical manifestations of tumor progression. During surgical and combined treatment for locally advanced thymomas with pleural invasion, it is obvious that the parietal pleura should be more widely excised through total pleurectomy; and when planning radiation therapy, it is necessary to take into account the high likelihood of metastases in the parietal pleura and, if possible, to increase radiation fields.