Kidney, or renal, cancer refers to any type of cancer that involves the kidney. Older age, obesity, smoking, and high blood pressure increase the risk of developing kidney cancer.
The kidneys are part of the urinary system, which eliminates waste and excess fluid and electrolytes from the blood. They also control the production of red blood cells and regulate blood pressure.
Kidney cancers mainly originate in two parts of the kidney, the renal tubule and the renal pelvis. A cancer that starts outside the kidney and metastasizes to the kidney is not normally called kidney cancer.
Around 63,990 new cases of kidney cancer are diagnosed in the United States each year, causing over 14,000 deaths annually. In 2017, 40,610 American men and 23,380 women were expected to receive a diagnosis of kidney cancer.
Kidney cancer is one of the 10 most common cancers, affecting about 1 in every 63 people over a lifetime. It occurs more frequently among adults aged between 50 and 80 years.
Worldwide, North America has the highest rate of kidney cancer, but in developing countries, the incidence has been steadily increasing over the last three decades. This increase may be linked to a parallel rise in obesity rates, or it could be due to improved detection and diagnosis.
In many cases, the cause of kidney cancer is not known. In some other cases (such as with inherited conditions that raise kidney cancer risk), even when the cause is known it may not be preventable. But there are some ways you may be able to reduce your risk of this disease.
Cigarette smoking is responsible for a large percentage of cases, so stopping smoking may lower your risk.
Obesity and high blood pressure are also risk factors for renal cell cancer. Maintaining a healthy weight by exercising and choosing a diet high in fruits and vegetables, and getting treatment for high blood pressure may also reduce your chance of getting this disease.
Finally, avoiding workplace exposure to harmful substances such as cadmium and organic solvents may reduce your risk for renal cell cancer.
Symptoms do not usually appear in the early stages of kidney cancer.
In the later stages, the person may experience:
•blood in the urine
•a lump or mass in the back, near the kidneys
Less often, there may be:
•a continuous pain in the side, near the kidneys
•a lump in the abdomen
•constant fever and night sweats
•tiredness or fatigue
•weight loss and loss of appetite
Other conditions can lead to similar symptoms, so it is important to see a physician if any of these occur.