Symptoms and causes

Symptoms

Kidney cancer rarely causes signs or symptoms in its early stages. And currently there are no routine tests used to screen for kidney cancer in the absence of symptoms. In the later stages, kidney cancer signs and symptoms may include:

  • Blood in your urine, which may appear pink, red or cola colored
  • Pain in your back or side that doesn't go away
  • Loss of appetite
  • Unexplained weight loss
  • Tiredness
  • Fever, which usually comes and goes (intermittent)

When to see a doctor

Make an appointment with your doctor if you have any persistent signs or symptoms that worry you.

Causes

It's not clear what causes renal cell cancer, the most common form of kidney cancer, though there are several risk factors.

Doctors know that kidney cancer begins when some kidney cells acquire mutations in their DNA. The mutations tell the cells to grow and divide rapidly. The accumulating abnormal cells form a tumor that can extend beyond the kidney. Some cells can break off and spread (metastasize) to distant parts of the body.

Risk factors

Factors that can increase the risk of kidney cancer include:

  • Older age. Your risk of kidney cancer increases as you age.
  • Smoking. Smokers have a greater risk of kidney cancer than nonsmokers do. The risk decreases after you quit.
  • Obesity. People who are obese have a higher risk of kidney cancer than people who are considered average weight.
  • High blood pressure (hypertension). High blood pressure increases your risk of kidney cancer.
  • Treatment for kidney failure. People who receive long-term dialysis to treat chronic kidney failure have a greater risk of developing kidney cancer.
  • Certain inherited syndromes. People who are born with certain inherited syndromes may have an increased risk of kidney cancer, such as those who have von Hippel-Lindau disease, Birt-Hogg-Dube syndrome, tuberous sclerosis complex, hereditary papillary renal cell carcinoma or familial renal cancer.
  • Family history of kidney cancer. Even in the absence of an inherited syndrome, people who have a strong family history of renal cell cancer have a greater risk of kidney cancer.
  • Exposure to certain substances in the workplace.This might include, for example, exposure to cadmium or specific herbicides.