Cost-Effectiveness of liquid biopsy screening for gastric cancer in the United States.

BACKGROUND: Despite the frequent late-stage diagnosis of gastric cancer (GC), the U.S. lacks a routine gastric cancer screening program. Liquid biopsy (LB), specifically blood-based tests, has emerged as a potential screening approach, but it is unclear whether such a strategy is cost-effective. We therefore evaluated the cost-effectiveness of liquid biopsy screening for GC in the U.S. METHODS: A Markov model was developed to compare no screening (current standard-of-care) and two liquid biopsy screening strategies. The study used a simulated cohort of 45-year-old individuals with average risk of gastric cancer. Primary model outcomes included life expectancy, quality-adjusted life-years (QALYs), total cost, and incremental cost-effectiveness ratios (ICERs). A strategy was considered cost-effective if the incremental cost-effectiveness ratio was less than the U.S. willingness-to-pay threshold of $100,000 per quality-adjusted-life-year gained. RESULTS: In the base-case analysis, LB screening strategies were not cost-effective, with an incremental cost-effectiveness ratio of $917,826 per QALY gained. Screening became cost-effective for high-risk subpopulations or when the per-test cost was approximately $89. CONCLUSIONS: This economic evaluation of LB for GC screening found that while LB strategies are effective in reducing cancer incidence and mortality, they are not cost-effective due to high test costs. Our findings could help inform the potential planning of future clinical validation studies for LB tests used for GC screening.