S1392 Cost-Effectiveness of Incomplete Gastrointestinal Metaplasia Surveillance in Gastric Cancer Screening

Abstract

Introduction: Gastric cancer in the United States has a grim prognosis with an overall 5-year survival rate of 32%. Unfortunately, in the U.S., there are no established guidelines for screening or surveillance of gastric cancer. Widespread endoscopic screening and surveillance of the general population in East Asian countries has demonstrated significant reductions in gastric cancer mortality, owing to the high gastric cancer prevalence in these regions. Given the low prevalence of gastric cancer in the western world (a 10-year risk of 1.6%, according to the AGA), screening the general population isn’t cost-effective. However, endoscopic surveillance of individuals with atrophic gastritis, intestinal metaplasia and dysplasia (high-risk) has been shown to detect early gastric cancer in western populations. We investigated the possibility of the cost-effectiveness of routine endoscopic surveillance of individuals with incomplete gastric intestinal metaplasia (iGIM), given the higher risk of gastric cancer in this group. Methods: A Markov state-transition model was designed to analyze the cost-effectiveness of biennial esophagogastroduodenoscopy versus no surveillance (current standard) in individuals with iGIM over 20 years using a healthcare payer perspective. - A Markov cohort simulation was then carried out on a hypothetical population of 1000 patients for both arms. Utility weights, transition rates and probabilities were derived from published literature. - Costs of esophagogastroduodenoscopy, surgery and cancer care were calculated using Medicare reimbursement. - A willingness-to-pay threshold of $100,000/QALY was used to determine cost-effectiveness. Results: Base Case analysis of the data revealed that the cost of care of non-cardia gastric cancer in the biennial endoscopic surveillance arm was $ 76,357 lesser than that of the no-surveillance arm. - The total cost of non-cardia gastric cancer care in the no surveillance arm was $263,430, while the total cost of care in the biennial surveillance arm was $187,073. - The surveillance arm demonstrated incremental cost savings of $6815 and an incremental QALY value of 0.076. The endoscopic strategy was found to be dominant. Conclusion: When using a willingness-to-pay threshold of $100,000/QALY to detect overall cost-effectiveness our study demonstrates that biennial endoscopic surveillance in those with iGIM is very cost-effective. Confirmatory research should be done before specific recommendations can be given but the results are encouraging.Figure 1.: Cost-effectiveness Acceptability Curve. The curve depicts the probability of cost-effectiveness of surveillance endoscopy at different willingness to pay thresholds. X-Axis (A): Willingness to pay in dollars. Y-Axis (B): % Iteration cost-effective.