Up to 80 percent of primary liver cancers worldwide are caused by viral hepatitis, a disease that leads to inflammation in this organ. Hepatitis is caused by infection with hepatitis A, B, or C viruses. Of these three, however, only people with chronic or persistent hepatitis B or C infection – and particularly those with cirrhosis (scarring of the liver) – are at increased risk of developing liver cancer.
Infection occurs through physical contact with blood or other bodily fluids of an infected person, such as through unprotected sex and sharing of infected needles, or from receiving blood transfusions prior to 1992.
Because primary liver cancer caused by viral hepatitis tends to develop slowly over the course of two to three decades, there are steps you can take to get screened for the infection and prevent it from becoming advanced.
In addition to chronic hepatitis B and C infection, factors that increase the risk for liver cancer include:
- Non-alcoholic fatty liver disease (NAFLD). In this condition, a type of fat called triglycerides accumulates in the liver, which can lead to liver injury (non-alcoholic steatohepatitis). NAFLD can cause cirrhosis and liver failure. It commonly occurs in people who are overweight or obese, or who have type 2 diabetes or a metabolic syndrome. The condition is emerging as an important risk factor for liver cancer in the United States, where obesity is on the rise.
- Cirrhosis of the liver caused by alcohol use. Consumption of alcohol also greatly increases the risk of cancer in people infected with the hepatitis B or C virus. People with viral hepatitis are strongly advised to refrain from consuming alcohol.
- Hemochromatosis, one of the most common genetic disorders in the United States in which the body absorbs too much iron from food. The condition is most often found in people of Irish descent.
- Exposure to arsenic, a naturally occurring substance sometimes found in drinking water, or to vinyl chloride, a chemical used in making certain plastics. Excess intake of male hormones or of anabolic steroids, a type of hormone that builds muscle.
- Ingestion of the food contaminant aflatoxin, a harmful substance generated by certain types of mold found on improperly stored grains and nuts; this is extremely rare in the United States.
Ways to Prevent Liver Cancer
Among the most effective ways to reduce the risk of developing liver cancer is to avoid exposure to the hepatitis B and C viruses. Vaccines for hepatitis B are commonly available for children and adults. If you are at risk for hepatitis B or C infection, consider undergoing a screening test.
If you have chronic hepatitis B, you might be a candidate for antiviral therapy, which can slow down progression of liver disease and decrease (although not eliminate) the risk of liver cancer.
Undetected and untreated, however, infection with the hepatitis B virus can lead to cirrhosis, liver failure, and cancer. While there is no vaccine for hepatitis C, appropriate treatment can eliminate the virus in up to 80 percent of individuals. Even more-effective treatments for hepatitis B are being explored.
You can also lower your risk for developing liver cancer by following a healthy diet with limited alcohol and getting regular physical exercise.
Schedule Liver Cancer Screenings
If you have cirrhosis of the liver or certain types of chronic liver disease, such as hepatitis B, you should undergo a regular screening for primary liver cancer with imaging such as an ultrasound.
When performed every six months, screening tests can help you and your doctor identify liver cancer at an early, treatable stage.