Urothelial Carcinoma of Renal Pelvis
High-grade papillary urothelial carcinoma invading renal parenchyma (pathologic stage pT3). There is extensive involvement of the kidney with tumor cells infiltrating in between glomeruli and renal tubules. Such cases may sometimes mimic primary renal parenchymal tumor (such as collecting duct carcinoma). Pathologic stage is the single most important prognostic factor for urothelial carcinomas of the upper urinary tract.