[Epidemiology, natural history, and risk factors of hepatocellular carcinoma]

Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver. It is the sixth most common malignancy worldwide and the third cause of cancer-related mortality. Approximately 90% of HCCs are associated with a known risk factor, mainly hepatitis B and cirrhosis which is a true precancerous state, whatever its cause. The incidence of HCC in a patient with cirrhosis is 3-5% per year. In eastern Asia and sub-saharan Africa the dominant risk factor is chronic hepatitis B infection (together with exposure to aflatoxin B1 in Africa). In developped countries, hepatitis C and alcohol use are the main risk factors, and the incidence of HCC is growing, owing probably to the hepatitis C epidemic, the increasing incidence of non alcoholic steatohepatitis (NASH) and the better prevention and treatment of other complications of cirrhosis. In France, NASH is currently the second cause of cirrhosis with HCC after alcohol. The high mortality of HCC is due to a late diagnosis at an advanced stage. This is why screening of high risk patients is a major issue. The current recommendation is a biannual liver ultrasonography for cirrhotic patients, but only 20% of all HCCs are today diagnosed during a surveillance program. Surgical resection, liver transplantation and radiofrequency ablation are the 3 validated curative treatments. In France, only one fourth of all HCC patients are treated with a curative intent. Most patients are therefore treated with palliative treatments that include chemoembolization, multi-kinase inhibitors (sorafenib) and in almost one third of cases only best supportive care. Much effort is needed to target at risk populations and implement strict surveillance protocols.