Viral hepatitis B and hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the sixth most common can- cer in the world, some 630,000 new cases being diagnosed each year. 82% of cases are related to viral hepatitis, 55% to hepatitis B virus (HBV), 89% of those in regions where HBV is endemic. There is a striking parallel between the geographical distribution of the rates of chronic HBV infection and that of HCC. In the majority of HCC cases (70-90%) there is underlying liver cirrhosis. However, because HBV is an oncogenic virus, it can cause HCC in the absence of cirrhosis. The annual risk of HBV-induced HCC varies according to the presence or absence of concomitant cirrhosis. In HBV carriers without cirrhosis, the risk is 0.02-0.3% in Caucasians and 0.4-0.6% per year in Asians. In those with cirrho- sis, the risk is 2.2% and 3.7% respectively in Caucasians and Asians.