Immunotherapy has emerged as a promising therapeutic approach for locally advanced gastric cancer (LAGC) [1–3]. However, due to variability in patient response to immunotherapy [1], reliable biomarkers are needed for the prediction of patient response before treatment initiation. Recently, research has identified deficient mismatch repair (dMMR) and microsatellite instability-high (MSI-H) as potential predictors of immunotherapy response in patients with LAGC [2]. The study by Tran-Minh et al. r…