Congenital Aneurysm of the Superior Vena Cava

We have reviewed four reported cases of aneurysmal dilatation of the superior vena cava and added a fifth case report. We wish to emphasize: (1) inclusion of mis rare lesion in the differential diagnosis of superior mediastinal mass; (2) the value of venous angiography in delineating the true nature of this lesion; and (3) the benign nature of this congenital malformation, which does not require specific therapy.