Causes of liver cancer
It's not clear what causes most cases of liver cancer. Most of the time when cancer is found in the liver it did not start there, but has spread to the liver from another part of the body (metastatic cancer). This can happen to people with advanced breast cancer, colorectal cancer, lung cancer, and many other cancers. But in some cases, the cause is known. For instance, chronic infection with certain hepatitis viruses can cause liver cancer.

Risk factors
A number of different factors can combine and make it more likely that a person will experience liver cancer. For example, liver cancer is more common in men than in women. This type of cancer is also much more commonly diagnosed in developing countries in sub-Saharan Africa and Southeast Asia than in the United States. Other risk factors include:

Age - Liver cancer most commonly affects either older adults or adults between 20 and 50 years old, depending upon geographic location.

Aflatoxins - Long-term exposure to aflatoxins, cancer-causing substances from a fungus that is absorbed by peanuts, wheat, soybeans, groundnuts, corn, and rice can increase the risk of liver cancer.

Anabolic steroids - Long-term use of these types of male hormones can slightly increase the risk of liver cancer.

Arsenic - In some parts of the world, drinking water is contaminated with arsenic, which increases the risk of liver cancer.

Birth control pills - Birth control pills may slightly increase the risk of liver cancer, although birth control pills are now made in a different way, and it is not known if the newer ones increase liver cancer risk.

Certain inherited liver diseases - Liver diseases that can increase the risk of liver cancer include hemochromatosis, autoimmune hepatitis and Wilson's disease.

Certain types of liver disease - The most common risk factor for liver cancer is infection with hepatitis B virus (HBV) or hepatitis C virus (HCV). People diagnosed with hepatitis A infection do not have an increased risk of liver cancer. Hepatitis infections, however, can lead to cirrhosis and are spread from person to person through sharing dirty needles (such as in drug use), unprotected sex, or childbirth. HBV and HVC can also be passed on through blood transfusions.

Cirrhosis - Cirrhosis can often lead to cancer as liver cells are damaged and replaced with scar tissue. Main causes of liver cirrhosis include alcohol abuse and hepatitis B and C.

Diabetes - Diabetes can increase the risk of liver cancer but is more common in diabetics who have other risk factors such as heavy drinking and/or hepatitis.

Gender - Men are more likely to be diagnosed with liver cancer than women.

Nonalcoholic fatty liver disease - An accumulation of fat in the liver increases the risk of liver cancer

Obesity - Being very overweight might increase the risk of getting liver cancer.

Race/ethnicity - Asian Americans and Pacific Islanders are among the highest risk groups for developing liver cancer, followed by American Indians/Alaska Natives and Hispanics/Latinos, African Americans, and whites.

Tobacco - Some studies have found a link between smoking and liver cancer, but the extent of this is not known.

Vinyl chloride and thorium dioxide (Thorotrast) - These chemicals can increase the risk for developing some types of liver cancer.

Liver cancer symptoms are typically difficult to notice in early stages meaning that tumors and growths might go undetected. So how can you tell if you have signs of liver cancer? Read here to learn more about the symptoms of liver cancer in the Liver Cysts Symptoms section that follows.