Kidney cancer occurs when cells in the kidney grow out of control. The cells clump together and form a malignant (cancerous) tumor. The most common type of kidney cancer is called renal cell cancer.

The kidneys are bean-shaped organs in the midsection of the body, above the waist. People have 2 kidneys, one on each side of their spine. Kidneys make urine, which is carried to the bladder by 2 tubes called ureters. The bladder stores urine until it leaves the body.

How common is kidney cancer?

About 31,000 Americans are diagnosed with kidney cancer each year. To compare this with other cancers, click here.

Who is at risk of getting kidney cancer?

Anyone can get kidney cancer, but it usually strikes people over age 50. And the risk goes up with age. People with a family history of kidney cancer have a higher risk.

How do you lower your risk of kidney cancer?

Quit smoking.
Try to achieve and maintain a healthy weight.

Click here for a list of things that affect kidney cancer.

What is the screening test?

There is no good screening test to find kidney cancer in its early stages. If you're concerned about kidney cancer, talk to a doctor about your risk.

What are the symptoms of kidney cancer?

In its earliest stages, kidney cancer may have no symptoms. But as the cancer grows, symptoms may include:

• Blood in the urine
• Tiredness
• Weight loss or loss of appetite
• Frequent fevers
• A pain in the side that won't go away
• Anemia (low number of red blood cells) or high blood pressure

These symptoms may also be caused by something less serious. Only a doctor can know for sure. If you have any of these symptoms, talk to a doctor.