Within epithelial tumors, the density of CTLA-4+ cells was higher in squamous cell (421 ± 469 cells/mm2) and urothelial carcinomas (418 ± 347 cells/mm2) than in adenocarcinomas (268 ± 375 cells/mm2) and renal cell neoplasms (256 ± 269 cells/mm2; Table 1). The gene discussed is CTLA4; the disease is urothelial carcinoma.