Abstract
There are only a few cases of primary mediastinal synovial sarcoma in the literature. Normally, they do not respond well to chemotherapy. In our case, a 30-year-old patient was admitted due to thoracic pain, dyspnea, orthopnea, cough, hoarseness and weight loss over a 3-month period as well as a dramatic worsening a week before the admission. A chest radiography showed a completely white left hemithorax and contralateral mediastinal shift; in addition, a chest tomography revealed a giant heterogeneous mediastinal mass, lung atelectasia and a small pleural effusion. The patient was submitted to Chamberlain procedure (biopsy) under local anesthesia and the diagnosis of a synovial sarcoma was obtained after immunohistochemical analysis. Due to his poor general condition, he received chemotherapy first, with a dramatic response, after what, the mass that had been reduced was removed surgically. After a 5-year- follow-up period there are no signs of disease recurrence.