Pathology-proven urinary bladder urothelial cell carcinoma, that is the most common primary neoplasm of the urinary bladder and the most common tumor of the entire urinary system.

For TNM staging, although CT is unable to distinguish between T1, T2 and T3a (microscopic extravesical spread), it can distinguish T3b tumors (stranding/nodules in perivesical fat) and T4 tumors (direct extension into adjacent structures/loss of normal fat plane).

MRI is the choice radiological modality in locally staging the urothelial cell carcinoma of the urinary bladder and is, in some instances, able to distinguish T1 from T2 tumors on T2 weighted images.