While liver cancer is more common in Asian and African countries, more than 40,000 Americans are predicted to get a liver or bile duct cancer (cholangiocarcinoma) diagnosis annually.
If you have risk factors for liver or bile duct cancer, it’s important to take action. At Banner MD Anderson Cancer Center, our team of liver and bile duct cancer specialists can help you understand your risk and evaluate your symptoms.
What Causes Liver and Bile Duct Cancers?
Liver and bile duct cancers are on the rise in the United States. These increases are due in part to increases in body weight and alcohol use, which can cause cirrhosis and liver scarring. Worldwide, the most common risk factor for liver cancer is chronic (long-term) infection with the hepatitis B (HBV) or hepatitis C (HBC) virus. These infections lead to a high risk of developing cirrhosis, chronic hepatitis and liver cancer.
Certain diseases, including chronic liver disease, diabetes and primary sclerosing cholangitis, which leads to scarring and hardening of the bile ducts, can increase the risk of developing bile duct cancer. Other risk factors include smoking, inherited conditions, like Lynch syndrome and cystic fibrosis, and choledochal cyst, an issue causing dilation and irregularities in the bile ducts that can be present at birth.
Liver Cancer and Bile Duct Cancer Risk Factors
Liver and bile duct cancer are on the rise in the United States. The more risk factors a person has, the greater the chance of developing liver cancer or bile duct cancer. However, many people with known risk factors for bile duct cancer or liver cancer do not develop the diseases.
Factors that may increase your risk of liver cancer or bile duct cancer include:
- Age: The average age at onset of liver cancer is 63 years and the average age at diagnosis of bile duct cancer is 70 to 72 (depending on the type).
- Heavy alcohol use: Alcohol is a leading cause of cirrhosis, the highest risk factor for liver cancer in the United States. People who drink a lot of alcohol are also more likely to get bile duct cancer, especially those who have liver problems caused by heavy alcohol use.
- Gender: Liver cancer and intrahepatic bile duct cancer are more common in men than in women.
- Ethnicity: Asian Americans and Pacific Islanders have the highest rates of liver cancer, followed by Hispanics/Latinos, American Indians/Alaska Natives, African Americans and Caucasians. In the United States, the risk of bile duct cancer is highest among Hispanic Americans.
- Chronic viral hepatitis: The most common risk factor for liver cancer and one common risk factor for bile duct cancer is infection with hepatitis B virus (HBV) or hepatitis C virus (HCV). These infections lead to cirrhosis of the liver.
- Cirrhosis: Most people who develop liver cancer or bile duct cancer have cirrhosis. Cirrhosis causes scarring on the liver, increasing the chance of liver cancer and bile duct cancer.
- Family history and genetics: People with a family history of liver cancer may be more likely to develop liver cancer. Some inherited liver diseases, such as hemochromatosis, cause cirrhosis and increase a person’s risk of developing the disease. Those with a family history of primary sclerosing cholangitis are at greater risk of developing bile duct cancer.
- Non-alcoholic fatty liver disease: A condition common in people who are obese. Fat collects in the liver, increasing the risk of liver cancer and bile duct cancer.
- Tobacco use: Smoking increases your risk of liver and bile duct cancers.
- High body weight: Having a high body weight can lead to fatty liver disease and cirrhosis, increasing your risk of developing liver cancer. The risk of bile duct cancer is higher for people who are overweight, due to a higher risk of bile duct stones and non-alcoholic fatty liver disease. Changes in certain hormones may also contribute to the increased risk.
- Diabetes: Type 2 diabetes has been linked with an increased risk of liver cancer, usually in patients who also have other risk factors such as heavy alcohol use, chronic viral hepatitis and high body weight. People with either Type 1 or Type 2 diabetes may be at a slightly higher risk of bile duct cancer, although the risk of bile duct cancer in a person with diabetes is still low.
- Aflatoxins: Poisons made from mold growing on food crops. Crops like peanuts, wheat, soybeans, corn and rice can be contaminated with aflatoxins and end up in food products. Long-term exposure to aflatoxins is a major risk factor for liver cancer.
- Certain rare diseases: Diseases that increase the risk of liver cancer include tyrosinemia, alpha1-antitrypsin deficiency, porphyria cutanea tarda, glycogen storage diseases, choledochal cysts and Wilson disease.
- Bile duct stones: Similar to but smaller than gallstones, bile duct stones can cause inflammation, increasing the risk of bile duct cancer.
- Exposure to Thorotrast (thorium dioxide): This radioactive substance was used as a contrast agent for x-rays until the 1950s and was shown to increase the risk for bile duct cancer.
- Certain inherited conditions: Cystic fibrosis, Lynch syndrome and other conditions caused by DNA changes passed from parents to children increase the risk of bile duct cancer.
- Inflammatory bowel disease: Crohn’s disease, ulcerative colitis and other inflammatory bowel diseases cause an increased risk of bile duct cancer.
How to Prevent Liver Cancer and Bile Duct Cancers
Liver and bile duct cancers have low survival rates compared to other cancers. However, you can reduce your risk of getting these diseases through early detection and healthy lifestyle habits.
There is no way to prevent liver or bile duct cancer completely, but you may be able to lower your risk by:
- Getting the hepatitis B vaccine if you have a drug dependency and share needles, have unprotected sex with multiple partners or are a nurse, doctor, dentist or other medical professional
- Getting treatment for viral hepatitis
- Moderating alcohol intake
- Stopping tobacco use - Banner MD Anderson’s Tobacco Recovery Program has resources to help you quit tobacco.
- Using a condom to reduce the risk of contracting hepatitis C (no vaccination available)
- Maintaining a healthy body weight
- Treating underlying conditions such as diabetes and hemochromatosis
Talk to your doctor if you’re at higher risk for liver cancer or if you’re experiencing any signs or symptoms. Regular screenings for at-risk individuals are vital to early diagnosis.