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Risk factors for kidney cancer
A risk factor is something that increases the risk of developing cancer. It could be a behaviour, substance or condition. Most cancers are the result of many risk factors. But sometimes kidney cancer develops in people who don’t have any of the risk factors described below.
Kidney cancer occurs most often in people older than 50. It is more common in men than in women.
Risk factors are generally listed in order from most to least important. But in most cases, it is impossible to rank them with absolute certainty.
|Known risk factors||Possible risk factors|
Significant evidence shows no link between coffee and tea and increased kidney cancer risk. Evidence also shows that drinking alcohol (up to 2 drinks a day) decreases risk of kidney cancer. However, it is important to remember that there is strong evidence that drinking alcohol increases the risk of several other cancers. Drinking alcohol should not be used to reduce the risk of kidney cancer.
Known risk factors
There is convincing evidence that the following factors increase your risk of kidney cancer.
Smoking tobacco increases the risk of kidney cancer. The risk of kidney cancer increases with the amount and length of time smoked.
Being overweight or obese increases the risk of renal cell carcinoma, the most common type of kidney cancer. Researchers are looking to understand exactly how being overweight or obese increases a person’s risk.
High blood pressure (hypertension) increases the risk of kidney cancer. This risk appears to be due to the condition itself and not the medicines taken to treat high blood pressure. It is not clear exactly how high blood pressure contributes to the increased risk.
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 people without a genetic condition. The tumours often occur in both kidneys (bilateral), and the person may have several tumours in each kidney. These genetic conditions are not very common. They account for only a small number (about 2%–4%) of all kidney cancers.
Von Hippel-Lindau syndrome (VHL) is a rare inherited disorder where people develop tumours and cysts in different parts of the body, including the kidney. About 35%–45% of people with VHL develop kidney tumours. Tumours usually appear during early adulthood. VHL increases the risk of developing clear cell carcinoma of the kidney.
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 in other parts of the body.
Hereditary leiomyomatosis renal cell carcinoma (HLRCC) increases the risk of developing non-cancerous tumours, called leiomyomas, in the skin or uterus. It also increases the risk of developing papillary renal cell carcinoma type 2 tumours. This type of kidney cancer tends to be aggressive and spreads (metastasizes) quickly.
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 carcinoma and clear cell carcinoma.
Tuberous sclerosis (TS) can cause non-cancerous 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 angiomyolipoma, chromophobe renal carcinoma and clear cell carcinoma.
End-stage kidney (renal) disease is when the kidneys are no longer able to remove waste products from the blood, so a person needs a kidney transplant or dialysis. Dialysis is a procedure that takes the place of the kidneys and removes waste products from the blood. People with end-stage kidney disease, especially those who need dialysis, have a higher risk of developing kidney cancer.
People on dialysis for a long time can develop cystscystsA sac in the body that is usually filled with fluid or semi-solid material. in their kidneys (acquired cystic kidney disease). Acquired cystic kidney disease 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 less than 6% of those people develop kidney cancer.
People who have had a kidney transplant also seem to have a greater chance of developing kidney cancer in the other (non-transplanted) kidney.
People who have a first-degree relative (parent, brother, sister or child) with kidney cancer have an increased risk of also developing kidney cancer. The risk is stronger if the relative is a brother or sister.
Trichloroethylene (TCE) is an industrial solvent mainly used to remove grease from metal. It is also sometimes used in dry cleaning. People who are exposed to TCE at work are at an increased risk of developing kidney cancer. The risk increases when people are exposed to higher levels of TCE.
Possible risk factors
The following factors have been linked with kidney cancer, but there is not enough evidence to show they are known risk factors. Further study is needed to clarify the role of these factors for kidney cancer.
Some studies have found an increased risk of kidney cancer in people who received radiation treatment for ankylosing spondylitis (a form of arthritis that affects the joints in the spine). Risk may also be increased in women who had radiation therapy for cervical cancer.
People who survived atomic bomb blasts may have a higher risk of developing kidney cancer, especially in later life.
Some studies have suggested that arsenic in drinking water may increase the risk of kidney cancer.
Some research has shown that workers exposed to cadmium, a heavy metal often found in batteries, may have a higher risk of developing kidney cancer.
Being exposed to printing processes has been linked to a higher risk of kidney cancer, but the exact cause of the higher risk has not been identified.
Some studies suggest that people who have had thyroid cancer have a higher risk of developing kidney cancer. These 2 cancers have similar types of cancer cells, so there may be a common biological cause, but more research is needed to understand this connection.
A horseshoe kidney is an uncommon birth defect where 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. A few studies have shown that people with a horseshoe kidney may have a higher risk of developing different types of kidney cancer, including renal cell carcinoma.
Some studies have suggested that women who have had surgery to remove their uterus (hysterectomy) have a higher risk of developing kidney cancer. The reason for this is not known.
Some studies show that people with diabetes, particularly type 2 diabetes, are more likely to develop kidney cancer.
Some studies have shown that taller people are at higher risk of developing kidney cancer. The taller a person is, the greater the risk of kidney cancer. Researchers think this increased risk may be due to the influence of growth and puberty hormones early in life.
Unknown risk factors
It isn’t known whether or not the following factors are linked with kidney cancer. It may be that researchers can’t show a definite link or that studies have had different results. Further study is needed to see if the following are risk factors for kidney cancer:
- diet (including fat, meat, sugars)
- being exposed at work to asbestos, lead, benzidine, coal tars, coke ovens or tetrachloroethylene (also known as perchloroethylene, or PCE)
- over-the-counter pain relievers called nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin, acetaminophen and ibuprofen
- physical inactivity
- hepatitis C virus infection
- second-hand smoke
Questions to ask your healthcare team
To make the decisions that are right for you, ask your healthcare team questions about risks.