The kidneys collect urine in a section called the pelvis. The pelvis and its subdivisions (calyces) empty urine into a tube called the ureter, which leads to the bladder. Cancer can grow in this urine collection system, but is uncommon.
As a group, renal pelvis and ureter cancers account for no more than 5% of all cancers of the kidney and upper urinary tract. They affect men more often than women and are more common in people older than 65.
Tumors of the renal pelvis and ureter are usually transitional cell cancers. Approximately 10% are squamous cell carcinomas.
