Upper Urinary Tract Cancer Definition
Upper urinary tract cancer (UTUC) includes malignancies originating in the renal pelvis and ureter. 1
Anatomic Components
Upper tract urothelial tumors specifically encompass:
- Renal pelvis tumors – malignancies arising from the pyelocaliceal cavities 1
- Ureteral tumors – cancers originating in the ureter 1
Epidemiologic Distribution
The anatomic distribution of urothelial carcinomas demonstrates that:
- 90-95% originate in the urinary bladder 1
- 5-10% occur in the upper urinary tract (renal pelvis and ureter combined) 1, 2
- Approximately 8% arise in the renal pelvis specifically 1
- The remaining 2% originate in the ureter and urethra 1
Among upper tract tumors specifically, approximately two-thirds are located in the renal pelvis and one-third in the ureter 3.
Histologic Considerations
Urothelial (transitional cell) carcinoma is the predominant histology in upper tract tumors 1. However, rare nonurothelial variants can occur, including:
These nonurothelial histologies represent only 1.9% of upper tract tumors but carry significantly worse prognosis, with median survival of 11.3 months and 1-year survival of only 46% 4.
Important Distinction
Upper urinary tract cancer does NOT include bladder cancer or urethral cancer, despite all arising from urothelium 1. These are classified separately, though they share common risk factors and can occur synchronously or metachronously in the same patient 1.