Chronic hepatitis C is a leading cause of hepatocellular carcinoma (HCC) worldwide.Interferon (IFN) ther-apy decreases the incidence of HCC in patients with chronic hepatitis C.Prevention of chronic-hepatitis-C-related HCC is one of the most important issues in current hepatology.We have previously reported that male gender and high titer of hepatitis C virus (HCV) RNA are predictive factors for the development of HCC in HCV-related cirrhosis.Clinical efforts at eradicat-ing or reducing the viral load may reduce the risk for HCC.Furthermore,because HCC often recurs after ablation therapy,we performed a trial of IFN in pa-tients with chronic liver disease caused by HCV to see whether IFN therapy decreases recurrence after abla-tion therapy of HCV-related HCC.By using IFN therapy as a secondary prevention,patients with HCC who had received complete tumor ablation showed better sur-vival,primarily as a result of the preservation of liver function and also probably prevention of recurrence.Postoperative IFN therapy appears to decrease recur-rence after ablation therapy such as radiofrequency ablation (RFA) therapy of HCV-related HCC.We believe that there is a survival benefit in secondary prevention using IFN therapy.However,a controlled study is es-sential to obtain conclusive evidence of the efficacy of this strategy. Chronic hepatitis C is a leading cause of hepatocellular carcinoma (HCC) worldwide.Interferon (IFN) ther-apy decreases the incidence of HCC in patients with chronic hepatitis C. Prevention of chronic-hepatitis-C-related HCC is one of the most important issues in current hepatology. We have previously reported that male gender and high titer of hepatitis C virus (HCV) RNA are predictive factors for the development of HCC in HCV-related cirrhosis. Clinical efforts at eradicat-ing or reducing the viral load may reduce the risk for HCC.Furthermore, because HCC often recurs after ablation therapy, we performed a trial of IFN in pa-tients with chronic liver disease caused by HCV to see whether IFN therapy diminished after abla-tion therapy of HCV-related HCC. By using IFN therapy as a secondary prevention, patients with HCC who had received complete tumor ablation target better sur-vival, primarily as a result of the preservation of liver function and also probably prohibition of recurrence .Postoperative IFN therapy appears to decrease recur-rence after ablation therapy such as radiofrequency ablation (RFA) therapy of HCV-related HCC. We believe that there is a survival benefit in secondary prevention using IFN therapy. However, a controlled study is es- sential to obtain conclusive evidence of the efficacy of this strategy.