Liver cancer happens when liver cells develop changes (mutations) in their DNA. A cell’s DNA is the material that provides instructions for every chemical process in your body. DNA mutations cause changes in these instructions. One result is that cells may begin to grow out of control and eventually form a tumor — a mass of cancerous cells.
Sometimes the cause of liver cancer is known, such as with chronic hepatitis infections. But sometimes liver cancer happens in people with no underlying diseases and it’s not clear what causes it.
Risk factors
Factors that increase the risk of primary liver cancer include:
- Chronic infection with HBV or HCV. Chronic infection with the hepatitis B virus (HBV) or hepatitis C virus (HCV) increases your risk of liver cancer.
- Cirrhosis. This progressive and irreversible condition causes scar tissue to form in your liver and increases your chances of developing liver cancer.
- Certain inherited liver diseases. Liver diseases that can increase the risk of liver cancer include hemochromatosis and Wilson’s disease.
- Diabetes. People with this blood sugar disorder have a greater risk of liver cancer than those who don’t have diabetes.
- Nonalcoholic fatty liver disease. An accumulation of fat in the liver increases the risk of liver cancer.
- Exposure to aflatoxins. Aflatoxins are poisons produced by molds that grow on crops that are stored poorly. Crops, such as grains and nuts, can become contaminated with aflatoxins, which can end up in foods made of these products.
- Excessive alcohol consumption. Consuming more than a moderate amount of alcohol daily over many years can lead to irreversible liver damage and increase your risk of liver cancer.
Prevention
Reduce your risk of cirrhosis
Cirrhosis is scarring of the liver, and it increases the risk of liver cancer. You can reduce your risk of cirrhosis if you:
- Drink alcohol in moderation, if at all. If you choose to drink alcohol, limit the amount you drink. For women, this means no more than one drink a day. For men, this means no more than two drinks a day.
- Maintain a healthy weight. If your current weight is healthy, work to maintain it by choosing a healthy diet and exercising most days of the week. If you need to lose weight, reduce the number of calories you eat each day and increase the amount of exercise you do. Aim to lose weight slowly — 1 or 2 pounds (0.5 to 1 kilograms) each week.
Get vaccinated against hepatitis B
You can reduce your risk of hepatitis B by receiving the hepatitis B vaccine. The vaccine can be given to almost anyone, including infants, older adults and those with compromised immune systems.
Take measures to prevent hepatitis C
No vaccine for hepatitis C exists, but you can reduce your risk of infection.
- Know the health status of any sexual partner. Don’t engage in unprotected sex unless you’re certain your partner isn’t infected with HBV, HCV or any other sexually transmitted infection. If you don’t know the health status of your partner, use a condom every time you have sexual intercourse.
- Don’t use intravenous (IV) drugs, but if you do, use a clean needle. Reduce your risk of HCV by not injecting illegal drugs. But if that isn’t an option for you, make sure any needle you use is sterile, and don’t share it. Contaminated drug paraphernalia is a common cause of hepatitis C infection. Take advantage of needle-exchange programs in your community and consider seeking help for your drug use.
- Seek safe, clean shops when getting a piercing or tattoo. Needles that may not be properly sterilized can spread the hepatitis C virus. Before getting a piercing or tattoo, check out the shops in your area and ask staff members about their safety practices. If employees at a shop refuse to answer your questions or don’t take your questions seriously, take that as a sign that the facility isn’t right for you.
Seek treatment for hepatitis B or C infection
Treatments are available for hepatitis B and hepatitis C infections. Research shows that treatment can reduce the risk of liver cancer.
Ask your doctor about liver cancer screening
For the general population, screening for liver cancer hasn’t been proved to reduce the risk of dying of liver cancer, and it isn’t generally recommended. People with conditions that increase the risk of liver cancer might consider screening, such as people who have:
- Hepatitis B infection
- Hepatitis C infection
- Liver cirrhosis
Discuss the pros and cons of screening with your doctor. Together you can decide whether screening is right for you based on your risk. Screening typically involves a blood test and an abdominal ultrasound exam every six months.