Epidemiology, natural history and pathogenesis of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the main type of primary liver cancers and the third most common cause of cancer mortality worldwide. In France, rising number between 5000 and 6000 cases are diagnosed each year. The major risk factor for hepatocellular carcinoma is chronic hepatitis: viral hepatitis B, viral hepatitis C, consumption of alcohol, hemochromatosis. Hepatocellular carcinoma is closely associated to liver cirrhosis, which is a true precancerous state. Because hepatocarcinogenesis is a long and heterogeneous process, there is still much to understand. Many genetic and epigenetic alterations are described leading to changes in cellular signalling cascades involved in regulation of growth, differentiation, apoptosis, motility. Hepatitis viruses play a direct oncogenic role through the interaction between viral and cellular proteins, which control cell homeostasis, or by the integration of hepatitis B virus genome into the host genome. Furthermore, hepatitis viruses play an indirect oncogenic role by causing chronic inflammation and hepatocyte regeneration related to viral hepatopathy. In expectation of a better understanding of hepatocarcinogenesis and new treatments, prevention from risk factors and ultrasonographic screening of patients with cirrhosis should increase prognosis. (C) 2010 Societe francaise de radiotherapie oncologique (SFRO). Published by Elsevier Masson SAS. All rights reserved.