Abstract
BACKGROUND: C-reactive protein (CRP) has begun to be used in clinical practice to predict the prognosis of cancer patients, but evidence on its prognostic role remains inconsistent. We performed a systematic review and meta-analysis to investigate the prognostic value of postoperative CRP among patients with gastric cancer. METHODS: We systematically searched PubMed, Embase, Web of Science, the Cochrane Library, Scopus, the Chinese National Knowledge Infrastructure (CNKI), Wan Fang Data, and the VIP Database for studies published from inception to April 30, 2025. Studies investigating the association between postoperative CRP and overall survival (OS) or recurrence-free survival (RFS) were included. Hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) for these outcomes were extracted for meta-analysis. RESULTS: Twelve eligible cohort studies, involving 9246 patients, were included in the meta-analyses. Elevated postoperative CRP was a significant predictor of OS and RFS in gastric cancer patients (HR:1.51, 95% CI:1.38-1.66; HR:1.44, 95% CI:1.27-1.63, respectively). CRP measured at a specific postoperative time point showed stronger prognostic value (HR:1.74, 95% CI:1.37-2.19), despite substantial heterogeneity, whereas peak postoperative CRP during hospitalization yielded a highly consistent and significant effect (HR:1.53, 95% CI:1.34-1.76). Notably, peak CRP measured within the first week after surgery served as an independent prognostic factor for both worse OS (HR:1.80, 95% CI:1.38-2.34) and RFS (HR:1.63, 95% CI:1.29-2.06) after multivariable adjustment, without heterogeneity. CONCLUSION: This study identifies postoperative CRP as a powerful and readily available prognostic indicator for patients undergoing radical gastrectomy for gastric cancer, with its peak level within the first postoperative week being of particular prognostic value. Future prospective studies should aim to establish the optimal timing and specific thresholds for postoperative CRP measurement, thereby facilitating its effective integration into routine clinical practice.