Hepatocellular Carcinoma - Risk Factors

Risk Factors

The main risk factors for hepatocellular carcinoma are;

• Alcoholism
• Hepatitis B
• Hepatitis C (25% of causes globally)
• Aflatoxin
• Cirrhosis of the liver
• Hemochromatosis
• Wilson's disease (while some theorize the risk increases, case studies are rare and suggest the opposite where Wilson's disease actually may confer protection)
• Type 2 Diabetes (probably aided by obesity)

The risk factors which are most important varies widely from country to country. In countries where Hepatitis B is endemic, such as China, Hepatitis B will be the predominant cause of Hepatocellular Carcinoma. Whereas in countries, such as the United States, where Hepatitis B is rare because of high vaccination rates, the major cause of HCC is Cirrhosis (often due to alcohol abuse).

The risk of hepatocellular carcinoma in type 2 diabetics is greater (from 2.5 to 7.1 times the non diabetic risk) depending on the duration of diabetes and treatment protocol. A suspected contributor to this increased risk is circulating insulin concentration such that diabetics with poor insulin control or on treatments that elevate their insulin output (both states that contribute to a higher circulating insulin concentration) show far greater risk of hepatocellular carcinoma than diabetics on treatments that reduce circulating insulin concentration. On this note, some diabetics who engage in tight insulin control (by keeping it from being elevated) show risk levels low enough to be indistinguishable from the general population. This phenomenon is thus not isolated to diabetes mellitus type 2 since poor insulin regulation is also found in other conditions such as metabolic syndrome (specifically, when evidence of non alcoholic fatty liver disease or NAFLD is present) and again there is evidence of greater risk here too. While there are claims that anabolic steroid abusers are at greater risk (theorized to be due to insulin and IGF exacerbation), the only evidence that has been confirmed is that anabolic steroid users are more likely to have hepatocellular adenomas (a benign form of HCC) transform into the more dangerous hepatocellular carcinoma.

When hepatocellular adenomas grow to a size of more than 6–8 cm, they are considered cancerous and thus become a risk of hepatocellular carcinoma. Although hepatocellular carcinoma most commonly affects adults, children who are affected with biliary atresia, infantilecholestasis, glycogen-storage diseases, and other cirrhotic diseases of the liver are predisposed to developing hepatocellular carcinoma.

Children and adolescents are unlikely to have chronic liver disease, however, if they suffer from congenital liver disorders, this fact increases the chance of developing hepatocellular carcinoma.

Young adults afflicted by the rare fibrolamellar variant of hepatocellular carcinoma may have none of the typical risk factors, i.e. cirrhosis and hepatitis.