Mounting evidences suggest that obesity is a risk factor for various cancers including hepatocellular carcinoma (HCC). A cohort study with a population of around 900,000, with 35 kg/m2 or higher body mass index (BMI) were observed to had 4.4 times as high risk of mortality from liver cancer in contrast to control group with normal BMI (18.5 -24.9 kg/m2). Similar findings were corroborated by another meta-analysis that showed the relative risk of liver cancer was more in overweight patients (1.17%) and obese patients (1.89%) in comparison to normal weight controls.

Obesity has also been considered as a cause of metabolic syndromes including insulin resistance, type 2 diabetes and nonalcoholic fatty liver diseases (NAFLD) including simple steatosis, non-alcoholic steatohepatitis (NASH), and cirrhosis. To validate these findings, a population-based case control study showed that diabetes tripled the risk of HCC. NAFLD, a hepatic manifestation of metabolic syndrome can also progress into cirrhosis and cause HCC, which is also assumed as the main cause of cryptogenic cirrhosis.

Besides obesity, chronic hepatitis B (CHB) is one of the most main causes of HCC, that affect almost 60% in Africa and Asia and around 20% in western countries. Moreover, the incidence rate of HCC was revealed to be 0.2% per year in inactive carriers, 0.6% in chronic hepatitis without cirrhosis patients, and 3.7% in compensated cirrhosis patients, among the patients infected by hepatitis B virus (HBV) in Asia. It has been observed that HBV-infected subjects have 100 times the risk of HCC in contrast to individuals without infection.

However, there is scarcity of studies evaluating the effect of obesity in the development of HCC in CHB patients. One such study examined the effects of obesity on development of HCC. The study enrolled a total of 102 CHB patients who had been treated with entecavir. The median follow-up period was 45.2 months, and the 1 year, 3 years, and 5 years, whereas the cumulative incidence rates of HCC were 0%, 5.3%, and 9.0%. However, the study had several limitations and require more data. Thus, it can be concluded that unlike in CHC patients, obesity had no association with HCC development in CHB patients.

Source: Jang BK. Does obesity increase the risk of hepatocellular carcinoma in chronic hepatitis B patients? Clin Mol Hepatol. 2016;22(3):336-338.