A case of thymoma protruding into the superior vena cava through the thymic vein.

We describe an unusual case of an invasive thymoma protruding into the superior vena cava and left brachiocephalic vein through the thymic veins in a 64-year-old patient. The tumor was resected with a bypass of the right brachiocephalic vein and right atrium. Although this type of growth form is rare for an invasive thymoma, this case suggests that in surgical procedures for thymomas, meticulous examination of the thymic veins is necessary to avoid leaving residual tumor.