[A case report of mediastinal teratoma complicated with cardiac tamponade]

A 10-year-old Japanese boy was admitted to our hospital with complaints of the sudden and severe chest pain having occurred when he caught a ball on his chest. A chest X-ray film and MRI made a diagnosis of cardiac tamponade caused by perforation into the pericardial sac of a mediastinal teratoma and pericardial drainage was carried out. Pericardial effusion showed cloudy yellow and CA 19-9 level in the effusion was 6, 538.2 U/ml. The tumor was extirpated after recovery of his general condition. The tumor was consisted of solid material (5 x 6 x 3 cm) and of cystic part (4 x 6 x 0.8 cm) involving of viscous yellowish fluid. Microscopic sections showed ulcer with bleeding, granulation and pancreatic tissue. Histopathological diagnosis was benign mature teratoma. Including this case, fourteen cases of mediastinal teratomas with cardiac tamponade have been reported and this is the youngest case. Pancreatic tissue were observed histopathologically in most cases and it was thought that autodigestion by digestive enzyme from pancreas was major cause of perforation of the tumor into the pericardial sac.