Kidney Cancer

About 50,000 people in the United States are diagnosed with kidney cancer every year. The kidneys are a pair of kidney bean-shaped organs, located above the waist on either side of the spine, that filter and clean blood and produce urine.

The most common adult kidney cancer is renal cell carcinoma, which forms in the lining of small tubes in the kidney. Children usually develop a different form of kidney cancer called Wilms’ tumor.

In its early stages, kidney cancer usually causes no obvious signs or troublesome symptoms. As a kidney tumor grows, symptoms may occur. These may include:

  • Blood in the urine. In some cases, blood is visible. In other instances, traces of blood are detected in a urinalysis, a lab test often performed as part of a regular medical checkup.
  • A lump or mass in the kidney area.

Other less common symptoms may include:

  • Fatigue
  • Loss of appetite
  • Weight loss
  • Recurrent fevers
Reviewed by health care specialists at UCSF Medical Center.