Any substance or condition that increases cancer risk is referred to as a risk factor. There isn’t a known, single cause of kidney cancer (renal cell carcinoma). Most cancers are the result of many risk factors. However, some people with kidney cancer do not have any identifiable risk factors.
*Risk factors are generally listed in order from most significant to least significant. In most cases, it is impossible to rank the relative significance of individual risk factors with absolute certainty.
Kidney cancer occurs most often in people older than 50 years of age. It is more common in men than in women.
The following factors are known to increase the risk of developing kidney cancer.
Smoking
Smoking tobacco increases the risk of developing kidney cancer. The risk of kidney cancer increases with the amount smoked.
Back to top
Being overweight or obese
Being overweight or obese increases the risk of renal cell carcinoma. Researchers do not know exactly how being overweight or obese increases a person’s risk of developing kidney cancer.
Back to top
High blood pressure
High blood pressure (hypertension) increases kidney cancer risk. This risk appears to be due to the condition itself and not to the medicines taken to treat high blood pressure. It is unclear exactly how high blood pressure contributes to increased kidney cancer risk.
Back to top
Certain inherited genetic conditions
Some inherited (hereditary) genetic conditions increase the risk of developing different types of kidney cancer. People with these genetic conditions develop kidney cancer at a younger age than other people without a genetic condition. The tumours often occur in both kidneys (bilateral) and the person may have several tumours within each kidney. These genetic conditions are not very common and account for only a small number (about 2%–4%) of all kidney cancers.
Von Hippel-Lindau syndrome
Von Hippel-Lindau syndrome (VHL) is a rare inherited disorder in which people develop tumours and cysts in different parts of the body, including the kidney. Tumours usually appear during early adulthood. It is caused by a mutation in the VHL gene. VHL increases the risk of developing clear cell carcinoma of the kidney. About 35%–45% of people with VHL develop kidney tumours.
Hereditary papillary renal carcinoma (HPRC)
Hereditary papillary renal carcinoma (HPRC) is an inherited type of kidney cancer, where people develop many papillary renal cell carcinoma tumours in both kidneys. It is also known as papillary renal cell carcinoma type 1. Tumours only develop in the kidney and not other parts of the body. HPRC is most often linked to a mutation of the MET proto-oncogene.
Hereditary leiomyomatosis renal cell carcinoma
People with hereditary leiomyomatosis renal cell carcinoma (HLRCC) are at risk of developing papillary renal cell carcinoma type 2 tumours, as well as benign smooth muscle tumours, called leiomyomas, in the skin or uterus. This type of kidney cancer tends to be aggressive and spreads (metastasizes) quickly. HLRCC is linked to a mutation in the fumarate hydratase (FH) gene.
Birt-Hogg-Dube syndrome
Birt-Hogg-Dube (BHD) syndrome is a very rare genetic condition that affects the skin and lungs. It also increases the risk of certain types of tumours, including cancerous and non-cancerous kidney tumours. People with BHD can develop different types of kidney cancer, such as chromophobe renal cell carcinomas, oncocytic renal carcinomas and clear cell carcinomas. The gene linked to BHD is known as folliculin (FLCN).
Tuberous sclerosis
Tuberous sclerosis (TS) is another genetic condition caused by 2 faulty genes, TSC1 and TSC2. About 1 in 3 cases are inherited. It can cause benign tumours to form in many organs of the body, including the eyes, skin, brain, lungs, heart and kidneys. People with TS have an increased risk of developing kidney cysts and kidney cancer. They may develop renal angiomyolipomas, chromophobe renal tumours, as well as clear cell carcinomas.
Back to top
End-stage kidney disease and dialysis
People with end-stage kidney (renal) disease, especially those who need dialysis, have a higher risk of developing kidney cancer. Dialysis is a procedure that removes waste products from the blood when the kidneys do not work properly. People on dialysis for a long time can develop cysts in their kidneys (acquired cystic kidney disease). Acquired cystic disease of the kidney in turn increases the risk of kidney cancer. The risk of kidney cancer appears to increase the longer a person is on dialysis.
Less than half of people on long-term dialysis develop kidney cysts, and fewer than 6% of those people develop kidney cancer.
People who have had a kidney (renal) transplant also seem to have a greater chance of developing kidney cancer in the other (non-transplanted) kidney.
Back to top
Family history
Studies have shown that people with a first-degree relative (parent, brother, sister or child) diagnosed with kidney cancer have an increased risk of developing it themselves. Having a first-degree relative with kidney cancer roughly doubles the risk of developing kidney cancer.
Back to top
Horseshoe kidney
A horseshoe kidney is an uncommon birth defect in which the tissue forming the kidneys does not divide into 2 separate kidneys. Instead, one large, U-shaped kidney is formed, usually joined at the bottom. Different types of kidney cancer have been reported in people with this defect.
Back to top
Possible risk factors
The following factors have some association with kidney cancer, but there is not enough evidence to say they are known risk factors. Further study is needed to clarify the role of these factors for kidney cancer.
- exposure to radiation – Some studies have found an increased risk of kidney cancer in people treated with radiation therapy and in those exposed to radiation from atomic bombs.
- Women who received radiation treatment for cervical cancer may have a higher risk of developing kidney cancer.
- People who were treated with radiation therapy for ankylosing spondylitis (a form of arthritis that affects the joints in the spine) may be at an increased risk of developing kidney cancer.
- Atomic bomb survivors may have an increased risk of developing kidney cancer.
- arsenic in drinking water – Some studies have found an increased risk of kidney cancer in people who drink water that contains arsenic.
- occupational exposure to cadmium – Kidney cancer is generally not considered an occupational disease, but researchers have found an association with certain occupational exposures. Some studies have suggested that people who are exposed to cadmium (a metal often found in batteries) at work may be at a higher risk of developing kidney cancer.
- occupational exposure to trichloroethylene – Trichloroethylene (TCE) is an industrial solvent mainly used in metal degreasing. It is sometimes used in dry cleaning. Recent studies have reported an increased risk of kidney cancer with TCE exposure. The risk tends to increase with higher levels of exposure.
- occupational exposure in printing processes – Occupational exposure to printing processes has been linked to kidney cancer. Some studies have found an increase in kidney cancer in employees working in the printing industry.
Back to top
Factors not associated with kidney cancer
The following are not considered to be risk factors for kidney cancer because there is enough evidence showing that there is no association:
Back to top
Unknown risk factors
The following are factors for which there is not enough evidence or the evidence is inconclusive. In other words, it can’t be determined for sure whether these risk factors are or are not associated with kidney cancer.
- diabetes
- second-hand smoke
- physical inactivity
- occupational exposure to certain chemicals
- asbestos
- benzidine
- coal tars or coal-tar pitches
- coke oven emissions
- gasoline
- lead
- tetrachloroethylene (also known as perchloroethylene or PCE)
- diet
- women’s reproductive and hormonal factors
- kidney stones or infections
- phenacetin and over-the-counter pain-relieving (analgesic) medicines (such as aspirin, acetaminophen or ibuprofen)
Back to top
See a list of questions to ask your doctor about risks. Find out how to reduce the risk of kidney cancer.