Abstract
BACKGROUND: Gastric cancer remains a major cause of cancer-related mortality in intermediate-risk countries. Although endoscopic screening is widely implemented in high-risk regions, its effectiveness and economic viability in intermediate-risk settings remain uncertain. This systematic review and meta-analysis evaluated the effectiveness and cost-effectiveness of endoscopic screening in these countries. METHODS: A systematic review and meta-analysis was conducted to assess the effectiveness and cost-effectiveness of upper gastrointestinal endoscopic screening by esophagogastroduodenoscopy (EGD) for gastric cancer. Searches were performed in Medline, Scopus, Embase, and Web of Science up to 30 September 2024. Pooled estimates were calculated for the detection of precancerous conditions, gastric cancer (overall and early-stage), and gastric cancer-specific mortality. Subgroup analyses were performed by screening strategy and geographic setting. RESULTS: Thirty-two studies met inclusion criteria-24 on screening effectiveness and eight on cost-effectiveness. Among 404,159 individuals screened, the pooled detection rate for precancerous conditions was 25.5%, for gastric neoplastic lesions 3.3%, and for early-stage cancer among neoplastic cases 91.6%. Gastric cancer-specific mortality was 26.1%, and 5-year survival reached 75.7%. Subgroup analyses of studies using direct EGD versus pre-selection indicated higher detection of precancerous conditions (32.5% vs. 17.0%, p < 0.001) and early-stage cancer (95.8% vs. 87.3%, p < 0.001). Comparing Chinese versus other settings, similar detection rates were found for precancerous conditions (25.3% vs. 26.0%) and early-stage detection (91.5% vs. 100%). Economic analyses suggest that endoscopic screening is cost-effective in intermediate-risk settings, particularly when combined with colorectal screening, with incremental cost-effectiveness ratios within accepted willingness-to-pay thresholds. CONCLUSIONS: Endoscopic screening by EGD shows strong potential for early detection of gastric cancer in intermediate-risk countries. However, formal comparative analyses with unscreened populations are lacking, and most survival and mortality data originate from Chinese studies, limiting generalizability. Nevertheless, economic evaluations suggest implementing endoscopic screening-especially when integrated with colorectal screening or guided by risk stratification-could be a feasible and effective strategy. TRIAL REGISTRATION: PROSPERO-CRD42024502174.