Surgical excision for mediastinal synovial sarcoma with limited response to chemoradiotherapy

Primary synovial sarcoma of the mediastinum is an exceedingly rare neoplasm. We describe a 31-year-old woman who had an incidental diagnosis of mediastinal mass. Histopathology and immunohistochemistry analysis confirmed the diagnosis of primary mediastinal synovial sarcoma. The patient underwent concurrent chemotherapy and radiotherapy, with minimal response radiologically. Resection was subsequently performed, with negative margins. The histopathologic examination revealed the diagnosis with a limited pathologic response. Because of the rarity of primary mediastinal synovial sarcoma, the optimal therapy is still unclear. We report this case of induction therapy followed by en bloc surgical resection.