Recurrence of a Pericardial Mass Initially Diagnosed as Haemangioma: A Case of Synovial Sarcoma in a Young Male

We present a rare case of synovial sarcoma of the pericardium in a young male, initially misdiagnosed as a benign haemangioma. The patient underwent surgical excision of the pericardial mass with a provisional diagnosis of haemangioma. However, recurrence occurred within a year, prompting re-evaluation. Histopathology and immunohistochemistry of the recurrent mass confirmed the diagnosis of monophasic synovial sarcoma. This case highlights the diagnostic challenge posed by rare pericardial tumors and emphasizes the importance of thorough histological assessment. Early recognition and accurate diagnosis are crucial for appropriate management and to reduce the risk of recurrence and metastasis in such cases.