Cancer that started in the liver (primary liver cancer) is quite rare in the UK, but is increasing. We don’t know what causes most liver cancers. But there are some factors that might increase your risk of developing it.
Having any of these risk factors doesn’t mean that you will definitely develop cancer.
Cirrhosis means 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:
- 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
Primary biliary cirrhosis (PBC) is a long term liver disease where the bile ducts become damaged. This leads to a build up of bile in the liver, eventually causing cirrhosis of the liver. People with PBC have an increased risk of HCC.
Drinking more than around 5 units of alcohol a day increases the risk of liver cancer. This amount of alcohol is above the current government guidelines for alcohol intake. Long term heavy drinking causes cirrhosis, and may also directly damage the DNA in liver cells.
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 may lead to cirrhosis. Non alcoholic fatty liver disease is common in people who have a group of symptoms called metabolic syndrome, including:
- having extra weight around the waist
- using insulin less effectively than normal
- type 2 diabetes
- high blood pressure
One study has estimated that people with non alcoholic fatty liver disease have a risk of liver cancer that is 4 times higher than people without this condition.
Long term infection with hepatitis B or C virus increases the risk of developing primary liver cancer because it causes damage to the liver (cirrhosis). If you have hepatitis B or C infection, it is important not to drink alcohol. If you do drink, it can further increase your risk of developing cirrhosis or liver cancer.
Smoking increases the risk of liver cancer. Researchers estimate that almost a quarter of liver cancers in the UK are caused by smoking. In smokers who also have hepatitis C or hepatitis B virus infection the risk is increased further. Smokers who drink large amounts of alcohol may have a risk that is almost 10 times higher than people who don't smoke or drink.
Children whose parents smoked before or during pregnancy have an increased risk of a very rare type of liver cancer called hepatoblastoma.
HIV and AIDS lower immunity. An overview of individual studies showed that people with HIV or AIDS have a risk of liver cancer that is around 5 times higher than people who don't have HIV or AIDS.
After organ transplants, people have to take medicines to stop their body rejecting the transplant. These medicines lower immunity and people who take them have around double the usual risk of liver cancer. People who have a liver transplant appear to have an even greater risk of liver cancer. But this may be due to a previously undiagnosed cancer in the donor liver.
The increased risk of liver cancer in people with low immunity may be because they are less likely to clear hepatitis B or C infection.
Systemic lupus erythematosus (SLE) is a chronic condition that causes inflammation of the skin and joints, and may include organs such as the heart and kidneys. People with SLE have more than double the risk of liver cancer compared to the general population.
People with a family history of liver cancer have an increased risk of developing it themselves.
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
People who have their gallbladder removed (cholecystectomy) to get rid of gallstones may have an increased risk of liver cancer. The increased risk may be due to raised pressure in the bile duct causing long term inflammation in the liver tissue.
Radiation from X-rays or scans can increase the risk of liver cancer but the risk is still very small. It is important to remember that X-rays and scans are very important in diagnosing illness so that people can have the right treatment.
Being overweight or obese increases the risk of liver cancer. Diabetes and non alcoholic fatty liver disease are more common in people who are overweight, so this may partly explain the link.
Some studies have shown 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 a small amount of evidence that betel quid, even without the tobacco causes liver cancer. But more research is needed.
Aflatoxin is a substance found in mouldy peanuts, wheat, soya beans, groundnuts, corn and rice. People from Africa and Asia who have eaten these over a long period of time have an increased risk of developing hepatocellular liver cancer. The risk is increased further in people who also have chronic hepatitis B infection.
There is evidence that exposure to the chemical vinyl chloride increases liver cancer risk. There is also limited evidence that exposure to arsenic, polychlorinated biphenyls and trichloroethylene may increase risk. People may come into contact with these chemicals through their work.
For detailed information on liver cancer risks and causes
Other possible causes
Stories about potential causes are often in the media and 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.