Perioperative versus adjuvant chemotherapy for resectable gastric cancer: a meta-analysis of randomized controlled trials

Objectives: To report the latest systematic review and meta-analysis of randomized controlled trials (RCT) to compare perioperative versus adjuvant chemotherapy for resectable gastric cancer. Methods: We conducted a systematic literature retrieval via PubMed, Embase, Web of Science, and Cochrane until April, 2024 for RCT which compared perioperative versus adjuvant chemotherapy for resectable gastric cancer. Outcomes measured were overall survival (OS) and progression-free survival (PFS). Results: 5 RCTs including 2,735 patients were included for meta-analysis. Meta-analysis revealed a significant longer PFS in the neoadjuvant chemotherapy (NAC) group (HR: 0.77; 95% CI: 0.69, 0.85; P<0.00001) compared with adjuvant chemotherapy (AC) group. Subgroup analysis found that there was still a significant superiority of NAC in female (HR: 0.53; 95% CI: 0.40, 0.70; P<0.0001) and cN+ (HR: 0.77; 95% CI: 0.67, 0.89; P=0.0005) patients, while the superiority disappeared in male (HR: 0.87; 95% CI: 0.74, 1.01; P=0.07) and cN- patients (HR: 0.91; 95% CI: 0.46, 1.78; P=0.77). In addition, meta-analysis observed a trend towards improved OS with NAC (HR: 0.86; 95% CI: 0.70, 1.07; P = 0.17), and sensitivity analysis demonstrated instability in OS. Conclusions: NAC can significantly prolong PFS in patients with resectable gastric cancer compared to AC, and the benefit is more significant in women and cN+ patients. Besides, our analysis indicated that NAC has a potential to improve OS compared with AC. Systematic review registration https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42024546165.