Testicular tumor. A, Sectioned surface of testicular tumor shows an expansile hemorrhagic nodule displacing surrounding testicular tissue (gross). B, Angiosarcoma with classic architectural pattern composed of proliferation of anastomosing blood-filled channels, and focal solid pattern (hematoxylin-eosin, original magnification ×40). C, Angiosarcoma with classic architectural pattern composed of anastomosing small, apparently immature vascular channels, lined by crowded plump endothelial cells, proliferating in a fibromyxoid stroma (hematoxylin-eosin, original magnification ×200). D, Tumor cells with typical cytology of plump hyperchromatic, tufted endothelial cells with scant amphophilic cytoplasm. Note the presence of mitotic figures (hematoxylin-eosin, original magnification ×600).