Rare Case of Mediastinal Synovial Sarcoma in an Indonesian Woman

Background: Synovial sarcoma mediastinum is a rare tumor, with few cases having been reported.Case Presentation: A 27-year-old Indonesian woman had complaint of shortness breath and left chestpain. Chest X-ray showed massive pleural effusion reddish-yellow fluid. Thorax CT scanshowed clear demarcated mass in the anterior until medius, value lactic aciddehydrogenase 561 U/L. The patient was diagnosed mediastinal tumor performed anterolateralthoracotomy weight 2.354 mg. Tumor histopathology consisted positive Vimentin, BCL2and CD99 antibodies. 3 cycles chemotherapy after surgery using doxorubicin,ifosfamide, mesna. Post-chemotherapy results metastases hemidiaphragm withan expansion defects lymphadenopathy upper right paratracheal.Conclusion: prognosis synovial worse than other organsas seen most recurrent cases.