Figure 2. (A) Cross-sections of the thoracic descending aortic wall after removal of the stent graft. A crescent-shaped aneurysm-like mass with severe hemorrhage was shown along with aortic wall. This mass corresponded to the lesion shown in Figure 1. (B) Elastica van Gieson stain corresponding to the area surrounded by the red square in (A). The tumor (surrounded by blue dashed line) mainly located in the aortic wall and destroyed aortic media (black arrowheads) and focally invaded into the lung through the pleura (white arrowheads). Below the pleura was the aortic wall and above the pleura was the left lower lobe of the lung. Bars, (A) 10 mm, (B) 2 mm.