Types Definition of kidney cancer: Cancer that forms in tissues of the kidneys. Kidney cancer includes renal cell carcinoma (cancer that forms in the lining of very small tubes in the kidney that filter the blood and remove waste products) and renal pelvis carcinoma (cancer that forms in the center of the kidney where urine collects). It also includes Wilms tumor, which is a type of kidney cancer that usually develops in children under the age of 5. 
Estimated new cases and deaths from kidney (renal cell and renal pelvis) cancer in the United States in 2008:
- New cases: 54,390
- Deaths: 13,010