The exact manner in which the normal liver cells become cancerous is only partially understood. However, scientists believe that it involves damage to the DNA, and replication of cells with the same DNA error. Once this happens, it is too late to repair the damage that may eventually lead to a cancer.

Some of the risk factors are:

• Aflatoxin, which is a poisonous substance produced in a fungus which infects peanuts
• Chronic infection with hepatitis B & C viruses
• Alcohol abuse leading to scar tissue formation in the liver
• Inherited disorders that cause damage to the liver
• Certain chemicals like vinyl chloride, hydrocarbons, solvents, nitrites
• Long-term use of anabolic steroids
• Drinking water contaminated with arsenic

Most liver cancers can be prevented by public health measures that reduce exposure to these known risk factors.