Risks and causes of liver cancer
Your risk of developing cancer depends on many factors. These include your age, genetics, lifestyle and environmental factors.
Anything that can increase your risk of cancer is called a risk factor.
Primary liver cancer is uncommon in the UK, but rates are increasing. There are some factors that are known to increase your risk. Having one or more of the below risk factors doesn’t mean that you’ll definitely develop liver cancer.
Although liver cancer can happen at any age, it is most common in older people. Most people diagnosed are over the age of 60. The highest rates are in 85 to 89 year olds.
Cirrhosis is scarring of the liver due to previous damage. This scarring can cause problems with the way the liver works.
Having cirrhosis increases your risk of getting liver cancer (hepatocellular carcinoma or HCC). The risk varies depending on the cause of the cirrhosis. Cirrhosis can be caused by:
- long term infection with a virus such as hepatitis B or C
- long term alcohol drinking
- inherited diseases such as iron overload disorder (haemochromatosis) and alpha 1 antitrypsin deficiency
- non-alcoholic fatty liver disease
- primary biliary cirrhosis (PBC)
Smoking increases your risk of many different cancers, including liver cancer.
The risk of liver cancer is increased further if you smoke and drink a lot of alcohol. The risk might also be higher in people who smoke and have hepatitis B or C infection.
20 out of 100 cases of liver cancer in the UK are caused by smoking.
Being overweight or obese increases the risk of liver cancer. Diabetes and non alcoholic fatty liver disease (see below) are more common in people who are overweight. So this may partly explain the link.
More than 20 out of 100 cases of liver cancer (20%) in the UK are caused by being overweight or obese.
Heavy alcohol use increases your risk of liver cancer. Drinking alcohol long term can cause cirrhosis of the liver. Cirrhosis in turn increases the risk of liver cancer. Alcohol might also directly damage the DNA inside liver cells.
The risk of liver cancer is higher in heavy drinkers who have hepatitis B or C virus infections compared to those who drink moderate amounts of alcohol or don't drink at all.
7 out of 100 cases of liver cancer (7%) in the UK are caused by drinking alcohol.
Non alcoholic fatty liver disease
Having non alcoholic fatty liver disease increases your risk of liver cancer.
Non alcoholic fatty liver disease (NAFLD) is a group of conditions including mild hepatic steatosis and non alcoholic steatohepatitis. In these conditions fat builds up in the liver. The fat causes inflammation and damage, which might lead to cirrhosis. Non alcoholic fatty liver disease is common in people who have a group of symptoms (called metabolic syndrome). These include:
- having extra weight around the waist
- using insulin less effectively than normal
- high blood pressure
- high levels of fat in the blood
Infection with hepatitis viruses
Long term infection with the hepatitis B or C virus increases the risk of developing primary liver cancer. This is mainly because these viruses cause damage to the liver (cirrhosis).
Drinking alcohol when you have hepatitis B or C can further increase your risk of liver cancer.
People with diabetes have a higher risk of liver cancer than people who do not have diabetes. The higher risk may be due to the higher levels of insulin in people with diabetes or due to liver damage caused by the diabetes. The risk may be increased more in people who have other risk factors such as liver cirrhosis and hepatitis infection.
Some treatments for diabetes such as metformin may reduce the risk of liver cancer.
Human immunodeficiency virus (HIV) or AIDS
Studies have shown that people with HIV or AIDS have an increased risk of liver cancer. This might be because they have low immunity, which means the body is less able to fight infection. So they are less likely to clear a hepatitis B or C infection, which can cause cirrhosis.
Aflatoxin is a substance found in foods such as:
- mouldy peanuts
- soya beans
People from Africa and Asia who have eaten these over a long period of time have an increased risk of developing liver cancer. The risk is increased further in people who also have chronic hepatitis B infection.
There is some evidence that people who chew betel quid have an increased risk of liver cancer. Betel quid is a combination of betel leaf, areca nut and slaked lime. It may also contain tobacco. There is some evidence that betel quid, even without the tobacco causes liver cancer. But more research is needed.
Gallstones or gallbladder removal
People may have an increased risk of liver cancer if they:
- have had gallstones before, or
- had their gallbladder removed (cholecystectomy)
The increased risk may be due to raised pressure in the bile duct. This causes long term inflammation in the liver tissue.
There is evidence that exposure to the chemical vinyl chloride increases liver cancer risk. There is also limited evidence that exposure to other chemicals such as arsenic and trichloroethylene may increase risk. People may come into contact with these chemicals through their work.
People with a family history of liver cancer may have an increased risk of developing it themselves. This might be due to genetic or shared environmental factors.
Liver flukes (parasitic worms)
Liver flukes are infections caused by parasites. These infections can increase your risk of liver cancer. They are usually caused by eating contaminated food or drinking contaminated water. They are not common in the UK.
For detailed information on risk factors for liver cancer
We have more detailed information for health professionals about liver cancer risks and causes.
Other possible causes
There are often stories about potential causes in the media. It isn’t always clear which ideas are supported by evidence. There might be things you have heard of that we haven’t included here. This is because either there is no evidence about them, or it is less clear.