Synovial sarcoma of the heart: Report of a case with diagnosis by endoscopic ultrasound-guided fine needle aspiration biopsy.

Background Primary synovial sarcomas of the heart are aggressive and extremely rare tumors. At least 17 cases have been reported in the literature. In all the published cases the diagnosis was based on histoiogic sections. To our knowledge, this is the first case of primary synovial sarcoma of the heart diagnosed by fine needle aspiration (FNA). Case A 36-year-old male with an unremarkable past medical history presented with a 4.4-cm mass arising from the left ventricular wall of the heart. Endoscopic ultrasound guided fine needle aspiration biopsy of the mass revealed a high grade tumor showing an intimate admixture of spindle and epithelial cells. A diagnosis of undifferentiated sarcoma, favor synovial sarcoma, was rendered. Reverse transcription-polymerase chain reaction demonstrated the presence of a SYT-SSX fusion transcript. The patient received 6 cycles of chemotherapy followed by resection of the residual tumor. The histology of the viable tumor showed histotogic findings typical of biphasic synovial sarcoma. Conclusion Synovial sarcoma rarely presents as a primary tumor of the heart. Sampling by FNA allows demonstration of the cytomorphologic appearance typical of the tumor and other ancillary studies. The specific genetic abnormality of these tumors allows confirmation by cytogenetic and molecular studies.