2014 Volume 53 Issue 6 Pages 595-601
A 36-year-old man presented with near-syncope. He was found to have massive pericardial effusion with a giant pericardial tumorous lesion. The pericardial effusion exhibited a bloody nature; however, neither malignant cells nor infectious organisms were detected. 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) showed an increased uptake of FDG in the pericardial tumor only. Although the tumor was not resectable, thoracotomy and tissue sampling were performed. A histological analysis showed CD99 positivity and SYT gene rearrangement, leading to a diagnosis of synovial sarcoma arising from the left lateral pericardial surface. The patient is now receiving chemotherapy.