Prognostic Value of c-MET Protein Expression in Gastric Cancer Patients: A Systematic Review and Meta-Analysis

The heterogeneous nature of c-MET overexpression in gastric cancer (GC) leads to a lack of consensus on its prognostic significance. To evaluate the predictive value of c-MET protein expression in gastric cancer patients. A systematic review of studies from PubMed, Web of Science, Embase, and Cochrane Library up to April 2025. Heterogeneity and robustness were assessed using the Cochrane Q test, I² statistic, and sensitivity analysis. Publication bias was evaluated with Egger's and Begg's tests. The Newcastle-Ottawa Scale (NOS) assessed methodological quality. From 2,322 articles, 22 studies were included. High c-MET expression was significantly associated with reduced overall survival (OS) (Hazard Ratio [HR] = 1.22; 95% Confidence Interval [CI]: 1.13, 1.31; I² = 6.8%; P = 0.371) and disease-free survival (DFS) (pooled HR = 1.39; 95% CI: 1.11, 1.68; I² = 42.4%; P = 0.139). Definitions of c-MET positivity varied across studies regarding thresholds, staining intensity, and detection methods. Subgroup analysis of OS revealed conflicting conclusions based on study design, cutoff values, and c-MET assays. High c-MET expression may independently predict poor GC prognosis. Future efforts should focus on standardized detection methods and high-quality prospective studies to validate its prognostic value.