CD99 and urothelial carcinoma: The urothelial carcinoma component within the ureter, the tumor cells were positive for cytokeratin (Figure3c), epithelial membrane antigen, E-Cadherin and negative for Vimentin (Figure3d), S-100 and CD99, enhancing the contrast of synchronous urothelial carcinoma from mesenchymal chondrosarcoma.