Stereotactic Ablative Radiation Therapy for Sacral Bone Metastasis in Recurrent Type A Thymoma: A Two-Year Follow-Up Demonstrating Pain Reduction and Local Control.

A 74-year-old Asian man presented with sacral bone metastasis-related pain caused by a metastatic thymoma. Computed tomography revealed an approximately 6-cm sacral mass, which was confirmed as a metastatic thymoma. The patient was referred to our department and underwent stereotactic ablative radiation therapy (SABR) using volumetric modulated arc therapy and received a total dose of 35 Gy in five fractions. One year after SABR, the sacral lesion had decreased in size, and the pain medication was reduced. After two years, the patient no longer required pain medication, indicating successful management of bone metastases in recurrent Type A Thymoma.