Liver Cancer Risk Factors

A risk factor is anything that increases your chance of getting a disease, such as cancer. Different cancers have different risk factors. Some risk factors, like smoking, can be changed. Others, like a person's age or family history, can't be changed.

Having a risk factor, or even several risk factors, does not mean that you will get the disease. Some people who get the disease may have few or no known risk factors.

Several factors can increase a person's chance of getting hepatocellular carcinoma (HCC), the most common type of liver cancer.

Sex

Liver cancer is more common in men than in women. Much of this is probably because of behaviors affecting some of the risk factors described below.

Race/ethnicity

In the United States, Asian Americans and Pacific Islanders have the highest rates of liver cancer, followed by people who are Hispanic and Latino, American Indian and Alaska Native, African American, and White.

Chronic viral hepatitis

Worldwide, the most common risk factor for liver cancer is chronic (long-term) infection with hepatitis B virus (HBV) or hepatitis C virus (HCV). These infections lead to liver damage and are responsible for making liver cancer the most common cancer in many parts of the world.

HBV and HCV can spread from person to person through sharing contaminated needles (such as during IV drug use), unprotected sex, or childbirth. These viruses can also be passed on through blood transfusions, although this is very rare in the United States since blood products are tested for these viruses. In developing countries, children sometimes get infected with hepatitis B from prolonged contact with family members who are infected.

Other viruses, such as the hepatitis A virus and hepatitis E virus, can also cause hepatitis. But people infected with these viruses do not develop chronic hepatitis or cirrhosis and do not have an increased risk of liver cancer.

Symptoms of HBV and HCV infection

HBV is more likely to cause symptoms, such as a flu-like illness and jaundice (a yellowing of the whites of the eyes and skin). But most people recover completely from HBV infection within a few months. Only a very small percentage of adults become chronic carriers (and have a higher risk for liver cancer). Infants and young children who become infected have a higher risk of becoming chronic carriers.

HCV, on the other hand, is less likely to cause symptoms. But most people with HCV develop chronic infections, which are more likely to lead to liver damage or even cancer.

Cirrhosis

Cirrhosis is a disease in which liver cells become damaged and are replaced by scar tissue. People with cirrhosis have an increased risk of liver cancer. Most (but not all) people who develop liver cancer already have some evidence of cirrhosis.

There are several possible causes of cirrhosis. Most cases in the United States develop in people who drink a lot of alcohol or have chronic HBV or HCV infections.

Metabolic dysfunction-associated steatotic liver disease (MASLD)

Metabolic dysfunction-associated steatotic liver disease (MASLD), also known as non-alcoholic fatty liver disease (NAFLD), is a common condition in which fat builds up in the liver. This is more common in people with excess body weight. Some people with a subtype of this disease, known as metabolic dysfunction-associated steatohepatitis (MASH) or non-alcoholic steatohepatitis (NASH), might go on to develop cirrhosis.

Primary biliary cirrhosis

Some types of autoimmune diseases that affect the liver can also cause cirrhosis. For example, in primary biliary cirrhosis (PBC) the bile ducts in the liver are damaged, which can lead to cirrhosis. People with advanced PBC have a high risk of liver cancer.

Inherited metabolic diseases

Certain inherited metabolic diseases can lead to cirrhosis.

For example, people with hereditary hemochromatosis absorb too much iron from their food. The iron settles in tissues throughout the body, including the liver. If enough iron builds up in the liver, it can lead to cirrhosis and liver cancer.

Heavy alcohol use

Heavy alcohol use is a leading cause of cirrhosis in the US, which in turn is linked with an increased risk of liver cancer.

Tobacco use

Smoking increases the risk of liver cancer. People who smoked and stopped have a lower risk than those who still smoke, but both groups have a higher risk than those who never smoked.

Excess body weight

Having excess body weight increases the risk of developing liver cancer. This is probably because it can result in MASLD and cirrhosis (see above).

Type 2 diabetes

Type 2 diabetes has been linked with an increased risk of liver cancer, usually in people who also have other risk factors such as heavy alcohol use and/or chronic viral hepatitis. This risk may also be increased because people with type 2 diabetes tend to have excess body weight, which in turn can cause MASLD and other liver problems.

Certain rare diseases

Diseases that increase the risk of liver cancer include:

• Tyrosinemia
• Alpha1-antitrypsin deficiency
• Acute intermittent porphyria
• Porphyria cutanea tarda
• Glycogen storage diseases
• Wilson disease

Aflatoxins

These cancer-causing substances are made by a fungus that can contaminate peanuts, wheat, soybeans, ground nuts, corn, and rice. Storage in a moist, warm environment can lead to the growth of this fungus. Although this can occur almost anywhere in the world, it is more common in warmer and tropical countries. Developed countries, such as the US and those in Europe, test foods for levels of aflatoxins.

Long-term exposure to these substances is a risk factor for liver cancer. The risk is increased even more in people with hepatitis B or C infections.

Vinyl chloride and thorium dioxide (Thorotrast)

Exposure to these chemicals raises the risk of angiosarcoma of the liver (see What Is Liver Cancer?). It also increases the risk of developing cholangiocarcinoma (bile duct cancer) and HCC, but to a far lesser degree.

Vinyl chloride is a chemical used in making some kinds of plastics. Thorotrast is a chemical that in the past was injected into some patients as part of certain x-ray tests.

When the cancer-causing properties of these chemicals were recognized, steps were taken to eliminate them or minimize exposure to them. Thorotrast is no longer used, and exposure of workers to vinyl chloride is strictly regulated.

Anabolic steroids

Anabolic steroids are male hormones used by some athletes and other people to increase their strength and muscle mass. Long-term anabolic steroid use can increase the risk of liver cancer slightly. Cortisone-like steroids, such as hydrocortisone, prednisone, and dexamethasone, do not carry this same risk.