Hepatocellular carcinoma in the non-cirrhotic liver

Of hepatocellular carcinomas (HCC), 15-20% occur in the non-cirrhotic liver. All factors which cause HCC when liver cirrhosis (LC) is present, can also lead to HCC without LC. On the basis of the relative frequency, HCC can be roughly differentiated into 3 groups: 1) HCC, rarely occurring without cirrhosis (e.g. virus hepatitis, alcohol abuse). 2) HCC, frequently occurring without LC (alpha1-antiytrypsin deficiency, hemochromatosis, non-alcoholic fatty liver disease). 3) HCC, consistently occurring without LC (glycogen storage disease type 1, consumption of oral contraceptives/anabolic steroids). In groups 1 and 2 the level of hepatocellular toxicity necessary to reach LC is not yet achieved but the carcinogenic effect is already strong enough to induce HCC, possibly owing to the influence of additional carcinogens or host factors. In group 3, the carcinogenic effect is mediated by a long-standing alteration of the hepatocellular metabolism that is of low toxic effect and does not lead to cell death, but is nevertheless carcinogenic. In these cases, the initial formation of hepatocellular adenomas that subsequently transform into HCC is a common finding (adenoma-carcinoma sequence). © 2007 Springer Medizin Verlag.