The development of liver cancer is linked to several known risk factors including liver infections, cirrhosis, genetic disorders, lifestyle choices and toxin exposures. The American Cancer Society reports more than 22,500 Americans were newly diagnosed with liver cancer in 2009, with approximately 73 percent of cases diagnosed in men. Knowing the causes of liver cancer can aid in addressing modifiable risk factors, and instituting appropriate liver cancer surveillance among those at greatest risk for the disease.
Chronic Hepatitis B and C
Chronic hepatitis B and C infections are the leading cause of liver cancer in the United States, reports the American Cancer Society. The National Toxicology Program's "11th Report on Carcinogens" lists hepatitis B virus and hepatitis C virus as known cancer-causing agents in humans. In a 2010 article published in "Morbidity and Mortality Weekly Report," Dr. S. O'Connor and colleagues reported liver cancer incidence is on the rise in the United States. The authors note that chronic hepatitis B and C infections are responsible for approximately 78 percent of liver cancer worldwide.
Cirrhosis of the Liver
The National Cancer Institute reports cirrhosis of the liver is a known risk factor for the development of liver cancer, also known as hepatocellular carcinoma. Long-term, excessive alcohol intake is a frequent cause of liver cirrhosis in the United States. Hence, alcohol abuse is a contributing factor to the development of liver cancer.
Inherited Liver Diseases
Inherited liver diseases may be a contributing factor to the development of hepatocellular carcinoma, according to the American Cancer Society. Genetic disorders associated with increased liver cancer risk include hemochromatosis, Wilson's disease, alpha-1 antitrypsin deficiency, glycogen storage diseases, tyrosinemia and porphyria cutanea tarda.
Diabetes and Obesity
The American Cancer Society states that diabetes and obesity increase individual risk for liver cancer. The Cleveland Clinic reports that obesity and insulin resistance--the underlying metabolic disorder in type 2 diabetes--are strongly associated with fatty liver disease. Fatty liver disease may lead to chronic inflammation and liver damage. These factors may contribute to the increased risk for liver cancer seen in those with diabetes and obesity.
Toxin Exposure
The liver is the body's primary organ for detoxification of potentially injurious chemicals. As such, the liver is particularly vulnerable to toxin-induced damage. The American Cancer Society reports exposure to toxins including aflatoxins, thorium dioxide, vinyl chloride, arsenic and the many carcinogens contained in cigarette smoke increase the risk for development of liver cancer. In a 2009 article published in the "International Journal of Epidemiology," Dr. Y.C. Lee and colleagues reported current and former cigarette smokers have a significantly increased risk for liver cancer compared to those who have never smoked.
