Hepatocellular carcinoma (HCC) ranks among the 10 most common cancers worldwide. It evolves from several chronic liver diseases, most of which culminate in cirrhosis. As the most common causes, other than alcoholic cirrhosis, are chronic hepatitis B and C infections, its prevalence worldwide is linked to the prevalence of these two viruses. Thus, the highest rates are in southeast Asia and sub-Saharan Africa, the world's most populous nations, where hepatitis B virus infection is endemic. In most western countries, hepatitis C virus infection is the predominant cause, and hepatitis B-related liver cancer occurs largely among immigrants from countries of high hepatitis B endemicity. In most western countries, the incidence and mortality from HCC is increasing as a consequence of the chronic sequelae of the 'epidemic' of hepatitis C of the 1960-1980s. In the US, modeling of this infection predicts a continued rise in liver cancer over the next decade. Surveillance by the National Cancer Institute and the Centers for Disease Control confirms the increasing incidence of and mortality from HCC to the year 2000, although subsequent analyses suggest a slowing or possibly decline in the rate of increase. Whether this trend will continue requires further evaluation.