An unusual case of sudden unexpected death due to massive hemopericardium from primary mediastinal seminoma.

It is well-known that cardiovascular disease is the most common cause of sudden unexpected death, especially in the young. However complete postmortem investigation performed by qualified forensic pathologists is crucial in establishing the exact cause and manner of death. Sudden death caused by a cardiac tamponade occurring secondarily to a primary mediastinal tumor is extremely unusual. An autopsy on a 25-year-old man who died unexpectedly discovered a massive hemopericardium in association with an anterosuperior mediastinal mass. The tumor had invaded the pericardium and an ulcerative surface with hemorrhagic necrosis on the cut surfaces of the intrapericardial tumor was revealed. All cardiac chambers and intrathoracic great vessels were intact and both testes were normal. Histologic examination confirmed the diagnosis of primary mediastinal pure cell seminoma. Diffuse pulmonary edema, as well as generalized congestion of internal organs, was observed as evidence of acute decompensated heart failure. To our knowledge, this is the first reported case of unexpected death due to massive hemopericardium as a result of primary mediastinal seminoma.