Liver cancer rates doubled in the United States between 1976 and 2002, and is one of the most deadly cancers worldwide. A recent review article reported on the risk factors:
1. Hepatitis B or C virus infection. Worldwide, viral liver infections are the most common cause of liver cancer. Rates of hepatitis C infection are on the rise in the United States, and this is one contributing factor to the rising rates of liver cancer.
2. Alcohol. Liver damage is the most familiar hazard of excessive alcohol consumption. Cirrhosis is a common step on the way to liver cancer.
3. Obesity. A study of 28,129 individuals in Sweden showed a three-fold increase in liver cancer rates in obese patients. Excess weight is also associated with a higher mortality rate from this cancer. Rising rates of obesity may contribute to the increase in liver cancer rates.
4. Hereditary hemochromatosis. This is a fairly common genetic condition, found in up to one in 200 people of north European descent. However, it is not familiar to most of us. In women, the symptoms usually develop after age 50 and could be mistaken for peri-menopausal changes. Patients with hemochromatosis accumulate too much iron in the body, especially in the liver. This interferes with normal liver function. Symptoms range from mild to life-threatening. Patients are at increased risk for both liver cancer and liver failure. Blood tests can be used to diagnose this condition.
5. Diet. Red meat and high iron intake are associated with increased liver cancer risk, while vegetables and dairy products are associated with lower risk. Coffee is strongly associated with a lower risk. This could indicate that coffee has some protective benefit; however, coffee metabolism is impaired in cirrhotic livers, so it may be that people who are already at risk for liver cancer find coffee unpleasant.
6. Smoking. While lung cancer is a more familiar risk of smoking, other cancers including liver cancer are also associated with tobacco products.
7. Diabetes. Some studies indicate that diabetes is a risk factor independent of obesity and dietary factors, although more research is needed to quantify this factor.
8. Oral contraceptives. There is some evidence that long-term (more than five years) use of oral contraceptives may increase the risk of liver cancer. More research is needed in this area.
9. Betel quid. This is the nut of the Areca catechu palm, and is commonly chewed in some parts of the world.
10. Aflatoxin. This is a mold product common in foods that are cultivated in hot, humid climates or stored in warm damp conditions.
References:
1. Blonski W et al., “Non-viral causes of hepatocellular carcinoma”, World J Gastroenterol 2010 August 7; 16(29): 3603-15.
2. Hemochromatosis information online:
https://health.google.com/health/ref/Hemochromatosis
Linda Fugate is a scientist and writer in Austin, Texas. She has a Ph.D. in Physics and an M.S. in Macromolecular Science and Engineering. Her background includes academic and industrial research in materials science. She currently writes song lyrics and health articles.