Abstract
Synovial sarcoma is a malignant soft tissue tumor which most frequently affects the periarticular regions of the upper and lower extremities in young adults. We report a case of synovial sarcoma in the mediastinum, a rare location for the disease. A 73-year-old man was brought to our hospital with a complaint of chest and back pain. Chest computed tomography revealed a 62×52-mm cystic lesion at the aortopulmonary window, and surgical treatment was performed. The mass was located close to the aortic arch and pulmonary artery, and was incompletely resected due to severe adhesion. Apparent malignant findings could not be detected on intraoperative pathological examination. However, postoperative pathological examination demonstrated that the tumor consisted of biphasic elements of epithelial and spindle-shaped cells, and an abnormality of the SYT gene was detected on FISH, which confirmed the diagnosis of synovial sarcoma. Four cycles of adjuvant chemotherapy with ifosfamide were performed, and the remaining tumor was stable 17 months after surgery.
