Primary liver cancer is most commonly caused by cirrhosis, a disease linked to alcohol use, where healthy liver tissue is replaced by scar tissue, according to WebMD. Other causes of liver cancer include damage from hepatitis B and C and hemochromatosis, a disease that causes excess iron in the liver.
Primary liver cancer, also known as hepatocellular carcinoma, tends to occur in damaged livers, explains WebMD. The causes of a damaged liver include birth defects, alcohol abuse and chronic infection due to a variety of illnesses. Liver cancer has been linked to obesity and fatty liver disease, which occurs when the fat content of the liver is abnormally high.
Other than disease, a number of factors increase the risk for liver cancer, including various carcinogenic substances such as herbicides like vinyl chloride and arsenic; smoking; and hormones such as estrogen, notes WebMD. Other risk factors include sex, as men are more likely than women to have liver cancer; weight; and race, since Asian Americans and Pacific Islanders are more at risk.
Long-term use of anabolic steroids has been known to increase the risk of liver cancer, as does a history of diabetes. Liver cancer has also been linked to some rarer diseases, such as inherited metabolic diseases, tyrosinemia and Wilson's disease, states WebMD.