Long-Term Evaluation of Outcomes for Abdominal Ultrasound Screening for Hepatocellular Carcinoma

Background: Mass screening for hepatocellular carcinoma (HCC) with abdominal ultrasound (AUS) has been demonstrated in short-term follow-up in Taiwan, but long-term effectiveness and cost-effectiveness of AUS have not been well studied particularly when the recently emerging antiviral therapy has been introduced. The aim of this study is therefore to evaluate long-term outcomes of population-based organized service screening program without control group. Methods: AUS screening based on a risk score–guided invitation has been launched since October 2008 in Changhua. A total of 85,147 subjects aged 40-74 years attended the Changhua community-based integrated screening (CHCIS) program were targeted. Those with high score based on hepatitis virus infection, ALT, AST, type 2 diabetes, platelet count were invited to receive ultrasonography screening performed by board-certified gastroenterologists in town-based health center to identify liver cirrhosis, and suspected HCC cases. We developed a pseudo-control group by building up the disease natural history for HCC embedded with the risk prediction model and the survival by detection modes. The pseudo-control model was further used to the development of health economic decision model for cost-effectiveness of various preventive strategies. Results: We observed a 61% (RR = 0.39, 95% CI: 0.32-0.46) HCC mortality reduction with AUS by risk groups together with ∼30% coverage rate of antiviral therapy in an 8-year period. The simulated results indicates the additional contribution of 30% compliance rate of antiviral therapy (empirical estimate) to HCC mortality reduction was ∼22%. The corresponding figures were raised to 30% and 35% when the compliance rate of antiviral therapy was enhanced to 50% and 70%, respectively. The results of cost-effectiveness analysis shows the incremental cost-effectiveness ratio was $22,849 for the administration of AUS, and $101,849 for the administration of AUS plus 30% compliance to antiviral therapy. The corresponding figures for 50% and 70% compliance rate to antiviral therapy were $141,805 and $181,919, respectively. Conclusion: The population-based screening program for HCC together with antiviral therapy achieved HCC mortality reduction by 60%. The computer study design with a pseudo-control group on the basis of disease natural history of HCC embedded with the predictive model, and the survival part of HCC enables us to quantify the attributable proportion from different preventive regimes, and to estimate long-term effectiveness of the overall and marginal effectiveness and cost-effectiveness of AUS and antiviral therapy under different scenarios. Such approach provides the health policy-makers a reference for resource allocation.