It is known that there is a close relationship between cirrhosis and liver cancer. The proliferative phenomena characterizing liver cirrhosis seem to be predisposing factors for carcinoma. In fact, they differ from the self-limiting proliferative phenomena occurring in normal liver regeneration because they are associated with: 1) an abnormal hormonal pattern; 2) an altered arrangement of hepatocytes and non-parenchymal cells within the lobule; 3) an altered production of growth factors able to modulate liver regeneration; and 4) an abnormal oncogene expression. Under such conditions many carcinogens, which require the target cell to be in a replicative phase, have the opportunity to act.