Hepatocellular carcinoma (HCC) is a highly malignant tumour with a poor prognosis. Its incidence is rising. The estimate incidence worldwide is 1 million cases. Most frequently it develops in livers already affected by cirrhotic transformation. How cirrhosis predisposes for the development of HCC is not clear. It is probably associated with the increased DNA synthesis in regeneration nodules. In micronodular transformation (most frequently alcoholic) the incidence is less frequent than in the macronodular from (mostly posthepatitic). The relationship of HCC and viral hepatitis is beyond doubt-this applies in particular to hepatitis B and C. Chronic alcoholism must not be either. There the risk of development of HCC is four times higher than non-alcoholics. Toxins can be also important for the development of HCC (in particular aflatoxins, chlorinated hydrocarbons, pesticides). As to drugs, in particular anabolics and contraceptives are suspected. Smoking is also a risk factor. HCC is encountered also more frequently in some liver diseases caused by metabolic disorders. It is probable than the development of HCC is a multifactorial process with a marked component of liver transformation.

Keywords: Carcinoma, Hepatocellular /epidemiology/; Humans; Incidence; Liver Neoplasms /epidemiology/