Pericardial thymoma presenting as cardiac tamponade in an adult.

Thymoma is a rare tumour originating from the thymic epithelial cells. Here, we present a rare case of thymoma in a female patient in her early 60s, who presented for a clinical emergency. The tumour initially mimicked a primary pericardial tumour causing cardiac tamponade, but on surgical resection and subsequent histopathological examination, it was found to be a thymoma. This case emphasises the importance of considering thymoma as a possible aetiology in pericardial masses and highlights the diagnostic dilemmas associated with thymomas presenting in ectopic locations.