Liver cancer risk factors and prevention
Risk factors
A risk factor is anything that increases your chance of getting a disease. Different cancers have different risk factors. There are risk factors related to lifestyle (i.e. ones you can do something about) and risk factors that you cannot control.
Risk factors
There are many risk factors associated with all types of liver cancer. Some liver cancer risk factors are also risk factors for other types of cancer. The following table summarises risk factors for HCC and CCA*.
Anyone concerned about their risk of developing liver cancer should talk with their doctor about steps that they can take to monitor or reduce their own risk.
| HCC risk factor | CCA risk factor | |
|---|---|---|
| Liver Cirrhosis (when liver cells become damaged and are replaced by scar tissue): This is the most significant risk factor for liver cancer. Up to 90% of liver cancer cases occur in patients with underlying cirrhosis. | ✓ In 80–90% cases, people diagnosed with HCC have cirrhosis of the liver | ✓ |
| Chronic alcohol consumption: A person’s biological characteristics and the alcohol consumption context determines the level of risk. | ✓ | ✓ |
| Chronic Hepatitis B: A liver infection caused by the hepatitis B virus (HBV). This virus is transmitted through contact with infected blood and infected body fluids. It is most commonly transmitted from mother to child during birth and delivery. It is also transmitted through unprotected sex, injected-drug use that involves sharing needles, syringes, or drug-preparation equipment, and injury from needlesticks or sharp instruments. | ✓ | ✓ Associated with iCCA in particular |
| Chronic Hepatitis C: A liver infection caused by the hepatitis C virus (HCV). This is a bloodborne virus, therefore the most common modes of infection are through exposure to infected blood. This can be even very small amounts, e.g., through unsafe injection practices, unsafe health care and blood/blood product transfusions, and sexual practices that lead to exposure to blood. | ✓ | X |
| Obesity and being overweight: Compared to having a normal BMI (body mass index), being overweight is associated with a 21% increased risk of liver cancer. | ✓ | ✓ Obesity is associated with a 61% increase in risk of iCCA |
| Non-alcoholic fatty liver disease (NAFLD): This is the term for a range of conditions. It refers to a build-up of fat in the liver that is not caused by alcohol consumption. It is usually seen in people who are overweight or obese. | ✓ | ✓ |
| Age: Older age is a key risk factor for cancer. This is largely due to cell DNA damage accumulating over time. In the United States and Europe, the median age at diagnosis of liver cancer is 65 years. | ✓ | ✓ |
| Smoking: Cigarette smoking has been linked to a higher risk of several types of cancer. The risk increases with the number of cigarettes smoked per day and the number of years the person has smoked. | ✓ HCC risk is 66% higher in current smokers than in non-smokers. | ✓ |
| Family history/genetic factors: Anyone with a family history of liver cancer or liver disease is more at-risk of developing this themselves. | ✓ HCC risk is 155% higher in people with a family history of liver cancer. | ✓ |
| Primary sclerosing cholangitis (PSC): This is a disease of the bile ducts. The ducts become inflamed and this leads to scarring and narrowing of the ducts. | X | ✓ (25% develop CCA) |
| Liver flukes (liver parasite infection present mainly only in Southeast Asia) This infection causes inflammation, which ultimately leads to CCA. | X | ✓ |
| Birth defects/congenital disorders of the bile duct. For example, Caroli disease and choledochal cysts (enlargements of the bile ducts that can result in bile accumulation). | X | ✓ |
| Bile duct stones (hepatolithiasis and choledocholithiasis) | X | ✓ (associated with pCCA and/or dCCA) |
| Toxic chemical exposure | ✓ | ✓ |
| Diabetes Mellitus (a disease that affects how the body uses blood sugar (glucose)) | ✓ | ✓ |
*Please note that although multiple risk factors for CCA exist, most do not have a specific, identifiable risk factor.
