A Case of a Thymoma with Liver Metastases and Peritoneal Dissemination Surviving for 21 Years by Multidisciplinary Approach

Abstract

We report a female patient who had undergone extended thymectomy for a thymoma at 53 years of age. The tumor was histopathologically diagnosed as Type B3 + B2 thymoma according to the WHO classification. The patient received left hepatectomy for a liver tumor 9 years after the thymoma surgery. Although recurrent liver tumors were discovered 6 years after the liver resection, they disappeared by chemotherapy and radiation therapy. Two years after the liver recurrence, a gynecologist diagnosed her to have peritoneal dissemination of the thymoma (Type B3) by a biopsy, which was preoperatively suspected of a right ovarian tumor, but could not be resected due to abundant blood supply. We treated this disseminated tumor by radiotherapy and the tumor exhibited complete response. However, intraperitoneal tumors and a liver tumor newly appeared two years afterwards. Radiotherapy was very effective for those tumors, but new peritoneal and liver lesions persisted to grow. Multidrug chemotherapy was adopted and has been continued. More than 21 years or more than 12 years have elapsed after the thymoma surgery or after the resection of liver metastasis, respectively. There are few cases of liver metastases of a thymoma which were operated on and this is the only reported case of a thymoma of which peritoneally disseminated tumors were efficiently treated by radiotherapy. Multidisciplinary approach including surgical resection might contribute to long-term survival even for metastatic thymoma patient.