Risks and causes of liver cancer
How common liver cancer is?
Primary liver cancer is relatively rare in the UK, but it is increasing in number. Worldwide, it is the 6th most common cancer. The highest rates are in Eastern Asia.
Around 4,300 primary liver cancers are diagnosed in the UK each year. It is more common in men than in women. Our risk of liver cancer gets higher as we get older. Almost 9 out of 10 cases are diagnosed in people over the age of 55 years.
Primary liver cancer is cancer that started from the cells of the liver. It is much more common in the UK to have cancer that has spread into the liver from somewhere else in the body (secondary liver cancer). If you have secondary liver cancer, this is not the right section for you. You need to look for information in the section of this website that relates to your type of primary cancer.
What risk factors are
Anything that increases your risk of getting a disease is a risk factor. Different cancers have different risk factors. Doctors and scientists do not know exactly what causes liver cancer. But we know of some factors that can increase the risk.
Even if you have one or more risk factors, it doesn't mean that you will definitely get the disease. Researchers are investigating various factors that in the future may turn out to increase the risk.
Cirrhosis
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
Alcohol
Drinking more than 80g alcohol (about 10 units) a day over a number of years increases the risk of liver cancer. This amount of alcohol is well 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
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.
Infection with hepatitis viruses
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.
Hepatitis A and hepatitis E do not seem to increase the risk of liver cancer.
Smoking
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 up to 10 times higher than people who don't smoke or drink.
Low immunity
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 five 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 double the usual risk of liver cancer.
The increased risk of liver cancer may be because people with low immunity are more likely to become infected with hepatitis B or C.
Family history
An American study found that people who have a first degree relative (parent, brother or sister) diagnosed with liver cancer have double the risk of developing it. One study has also shown an increased risk of liver cancer in people with a father and brother diagnosed with prostate cancer.
Diabetes
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, drinking alcohol in large amounts, and hepatitis infection.
Some treatments for diabetes such as metformin may reduce the risk of liver cancer.
Gallbladder removal
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 CT scans
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.
Body weight
Two reviews have shown that the risk of liver cancer is higher in overweight and obese people. Diabetes and non alcoholic fatty liver disease are more common in people who are overweight, so this may partly explain the link.
The European Prospective Investigation into Cancer and Nutrition (EPIC) study is looking into links between diet and cancer. It found that the risk of liver cancer is higher in people who have a lot of weight around their waist (the apple shaped body).
Betel quid
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
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 hepatitis B infection.
Chemicals
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 do so. People may come into contact with these chemicals through their work.
Factors that may lower risk of liver cancer
Some research has shown that people who drink 1 or 2 cups of coffee a day may reduce their risk of liver cancer by 23% to 43%. But the evidence for this is limited.
How common liver cancer is?
Primary liver cancer is relatively rare in the UK, but it is increasing in number. Worldwide, it is the 6th most common cancer. The highest rates are in Eastern Asia.
Around 4,300 primary liver cancers are diagnosed in the UK each year. It is more common in men than in women. Our risk of liver cancer gets higher as we get older. Almost 9 out of 10 cases are diagnosed in people over the age of 55 years.
Primary liver cancer is cancer that started from the cells of the liver. It is much more common in the UK to have cancer that has spread into the liver from somewhere else in the body (secondary liver cancer). If you have secondary liver cancer, this is not the right section for you. You need to look for information in the section of this website that relates to your type of primary cancer.
What risk factors are
Anything that increases your risk of getting a disease is a risk factor. Different cancers have different risk factors. Doctors and scientists do not know exactly what causes liver cancer. But we know of some factors that can increase the risk.
Even if you have one or more risk factors, it doesn't mean that you will definitely get the disease. Researchers are investigating various factors that in the future may turn out to increase the risk.
Cirrhosis
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
Alcohol
Drinking more than 80g alcohol (about 10 units) a day over a number of years increases the risk of liver cancer. This amount of alcohol is well 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
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.
Infection with hepatitis viruses
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.
Hepatitis A and hepatitis E do not seem to increase the risk of liver cancer.
Smoking
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 up to 10 times higher than people who don't smoke or drink.
Low immunity
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 five 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 double the usual risk of liver cancer.
The increased risk of liver cancer may be because people with low immunity are more likely to become infected with hepatitis B or C.
Family history
An American study found that people who have a first degree relative (parent, brother or sister) diagnosed with liver cancer have double the risk of developing it. One study has also shown an increased risk of liver cancer in people with a father and brother diagnosed with prostate cancer.
Diabetes
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, drinking alcohol in large amounts, and hepatitis infection.
Some treatments for diabetes such as metformin may reduce the risk of liver cancer.
Gallbladder removal
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 CT scans
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.
Body weight
Two reviews have shown that the risk of liver cancer is higher in overweight and obese people. Diabetes and non alcoholic fatty liver disease are more common in people who are overweight, so this may partly explain the link.
The European Prospective Investigation into Cancer and Nutrition (EPIC) study is looking into links between diet and cancer. It found that the risk of liver cancer is higher in people who have a lot of weight around their waist (the apple shaped body).
Betel quid
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
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 hepatitis B infection.
Chemicals
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 do so. People may come into contact with these chemicals through their work.
Factors that may lower risk of liver cancer
Some research has shown that people who drink 1 or 2 cups of coffee a day may reduce their risk of liver cancer by 23% to 43%. But the evidence for this is limited.
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