Malignancy with unknown primary presenting as acute cardiac tamponade: a case report.

A case report of a patient presenting in cardiac tamponade that was subsequently diagnosed as being secondary to malignancy of unknown primary. The patient was treated by urgent pericardiocentesis, followed by subsequent formation of a subxiphoid pericardial window. He was discharged home and given palliative chemotherapy. Malignant pericardial effusions are common, but it is rare for a patient to present in cardiac tamponade as the presenting feature of an unidentified malignancy. The causes, diagnosis and treatment of cardiac tamponade are discussed.