What are the risk factors for kidney cancer?

A risk factor is anything that affects your chance of getting a disease such as cancer. Different cancers have different risk factors. For example, unprotected exposure to strong sunlight is a risk factor for skin cancer.

But risk factors don't tell us everything. Having a risk factor, or even several risk factors, does not mean that you will get the disease. And some people who get the disease may not have had any known risk factors. Even if a person with kidney cancer has a risk factor, it is often very hard to know how much that risk factor contributed to the cancer.

Scientists have found several risk factors that could make you more likely to develop kidney cancer.

Lifestyle-related and job-related risk factors

Smoking

Smoking increases the risk of developing renal cell carcinoma. The increased risk seems to be related to how much you smoke. The risk drops if you stop smoking, but it takes many years to get to the risk level of someone who never smoked.

Obesity

People who are very overweight have a higher risk of developing renal cell cancer. Some doctors think obesity is a factor in about 2 out of 10 people who get this cancer. Obesity may cause changes in certain hormones that can lead to renal cell carcinoma.

Workplace exposures

Many studies have suggested that workplace exposure to certain substances increases the risk for renal cell carcinoma. Some of these substances are asbestos, cadmium (a type of metal), some herbicides, benzene, and organic solvents, particularly trichloroethylene.

Genetic and hereditary risk factors

Some people inherit a tendency to develop certain types of cancer. The DNA that you inherit from your parents may have certain changes that give you this tendency to develop cancer. Some rare inherited conditions can cause kidney cancer. It is important that people who have hereditary causes of renal cell cancer see their doctors frequently, particularly if they have already had a renal cell cancer diagnosed. Some doctors recommend regular imaging tests (such as CT scans) for these people.

People who have the conditions listed here have a much higher risk for getting kidney cancer, although they account for only a small portion of cases overall:

von Hippel-Lindau disease

People with this condition often develop several kinds of tumors and cysts (fluid-filled sacs) in different parts of the body. They have an increased risk for developing clear cell renal cell carcinoma, especially at a younger age. They may also have benign tumors in their eyes, brain, spinal cord, pancreas and other organs; and a type of adrenal gland tumor called pheochromocytoma. This condition is caused by mutations (changes) in the VHL gene.

Hereditary papillary renal cell carcinoma

People with this condition have inherited a tendency to develop one or more papillary renal cell carcinomas, but they do not have tumors in other parts of the body, as is the case with the other inherited conditions listed here. This disorder is linked to changes in many genes, most often the MET gene.

Hereditary leiomyoma-renal cell carcinoma

People with this syndrome develop smooth muscle tumors called leiomyomas (fibroids) of the skin and uterus (in women) and have a higher risk for developing papillary renal cell cancers. It has been linked to changes in the fumarate hydratase (FH) gene.

Birt-Hogg-Dube (BHD) syndrome

People with this syndrome develop many small benign skin tumors and have an increased risk of developing different kinds of kidney tumors, including renal cell cancers and oncocytomas. They may also have benign or malignant tumors of several other tissues. The gene linked to BHD is known as folliculin (FLCN).

Familial renal cancer

People with this syndrome develop tumors called paragangliomas of the head and neck region, as well as tumors known as pheochromocytomas of the adrenal glands and other areas. They also tend to get kidney cancer in both kidneys before age 40. It is caused by defects in the genes SDHB and SDHD (succinate dehydrogenase subunit B and D, respectively).

These gene defects can also cause something called Cowden-like syndrome. People with this syndrome have a high risk of breast, thyroid and kidney cancers.

Hereditary renal oncocytoma

Some people inherit the tendency to develop a kidney tumor called oncocytoma, which has a very low potential for being malignant.

Other risk factors

Family history of kidney cancer

People with a strong family history of renal cell cancer (without one of the known inherited conditions listed previously) also have a 2 to 4 times higher chance of developing this cancer. This risk is highest in brothers or sisters of those with the cancer. It's not clear whether this is due to shared genes or something that both people were exposed to in the environment − or both.

High blood pressure

The risk of kidney cancer is higher in people with high blood pressure. Some studies have suggested that certain medicines used to treat high blood pressure may raise the risk of kidney cancer, but it is hard to tell if it's the condition or the medicine (or both) that may be the cause of the increased risk.

Certain medicines

Phenacetin, once a popular non-prescription pain reliever, has been linked to renal cell cancer in the past. Because this medicine has not been available in the United States for over 20 years, this no longer appears to be a major risk factor.

Diuretics: Some studies have suggested that diuretics (water pills) may be linked to a small increase in the risk of renal cell carcinoma. It is not clear whether the cause is the drugs or the high blood pressure they treat. If you need diuretics, you should take them. You shouldn't avoid them to try to reduce the risk of kidney cancer.

Advanced kidney disease

People with advanced kidney disease, especially those needing dialysis, have a higher risk of renal cell carcinoma. Dialysis is a treatment used to remove toxins from your body if the kidneys do not work properly.

Gender

Renal cell carcinoma is about twice as common in men as in women. Men are more likely to be smokers and are more likely to be exposed to cancer-causing chemicals at work, which may account for some of the difference.

Race

African Americans have a slightly higher rate of renal cell cancer. The reasons for this are not clear.