Image Description
Sarcomatoid urothelial carcinoma (also referred to as carcinosarcoma) is defined as a tumor containing both carcinoma as well as sarcomatous areas. The image shows high-grade urothelial carcinoma on the surface and a high-grade undifferentiated sarcoma underneath in the lamina propria. This was a recurrent bladder tumor in a 74 y/o male with long-standing history of high-grade papillary urothelial carcinoma.