This study aimed to investigate the prognostic significance of PIK3R1 in GC and its association with the tumor immune microenvironment.<h4>Methods</h4>PIK3R1 expression and its clinical relevance were analyzed using datasets from GC patients who underwent gastrectomy, including cohorts from The Cancer Genome Atlas (TCGA) and the Sun Yat-sen University Cancer Center (SYSUCC). The gene discussed is PIK3R1; the disease is neoplasm.