Kidney cancer starts in the kidneys, a pair of organs that lie in the back of your abdomen.
- Your kidneys make urine by removing waste and extra water from your blood.
- They also produce substances to help control blood pressure and to make red blood cells.
- At the top of each kidney is an adrenal gland. A layer of fatty tissue and an outer fibrous tissue surround the kidney and adrenal gland.
While kidneys are important, you actually need less than one complete kidney to function. Some people who do not have any working kidneys survive with the help of dialysis — using a specially designed machine that filters their blood.
Kidney cancers often do not cause symptoms in the early stages. When symptoms do occur, they may include:
- Blood in your urine.
- Low back pain.
- A mass or lump on the side or lower back.
- Loss of appetite.
- Weight loss.
- Recurrent fevers.
- Swelling of your ankles and legs.
Conditions other than cancer may cause the same symptoms as kidney cancer. If you have any symptoms that concern you, discuss them with your doctor.
Risk factors for kidney cancer include:
- Age. The risk of kidney cancer increases as you age. Kidney cancer occurs most often in people age 55 and older.
- Sex. Renal cell carcinoma (RCC) is about twice as common in men as in women.
- Smoking. Smokers are twice as likely to get kidney cancer as nonsmokers.
- Obesity and diet. Being overweight and having a high-fat diet increase your risk.
- Genetic and hereditary factors. Having kidney disease or a family history of kidney cancer puts you at greater risk.
- High blood pressure. Risk for kidney cancer is elevated in people with high blood pressure.
Five inherited diseases result from a faulty gene that increase kidney cancer risk:
- Von Hippel-Lindau syndrome.
- Birt-Hogg-Dube syndrome.
- Hereditary papillary RCC.
- Hereditary leiomyomatosis.
- RCC syndromes.