Efficacy and safety of chemoradiotherapy versus chemotherapy for resectable gastric cancer: a systematic review and meta-analysis.

Background: Gastric cancer is a leading cause of cancer-related deaths. Surgery combined with adjuvant treatments improves survival. This meta-analysis compares the efficacy of chemoradiotherapy (CRT) vs. chemoimmunotherapy (CT) in resectable gastric cancer.

Methods: A comprehensive search across five databases from inception to December 2024 identified studies on efficacy of CRT vs CT in adult patients with resectable gastric cancer. Data were pooled as odds ratio (OR) or hazard ratio (HR) with 95% confidence intervals (CI). Analysis used Review Manager 5.4 with a random-effects model.

Results: A total of 29 studies with 20 794 patients were included for further quantitative and qualitative analysis. CRT was associated with significantly higher recurrence-free survival (HR: 0.79; 95%CI: 0.69, 0.91; P = 0.004) and slightly improved overall survival (HR: 0.85; 95%CI: 0.73, 1; P = 0.05). The odds of locoregional metastases (OR: 0.60; 95%CI: 0.43, 0.82; P = 0.001) were significantly reduced following CRT. Adverse events between both treatments were comparable, although the risk of neutropenia (OR: 1.54; 95%CI: 1.29, 1.84; P<0.0001) and gastrointestinal side effects (OR: 1.30; 95%CI: 1.01, 1.69; P = 0.04) was significantly higher in the CRT arm.

Conclusion: This meta-analysis concludes a higher efficacy of CRT over CT in improving survival and preventing recurrence, while limiting regional metastasis. Further studies are needed to assess modulation of radiotherapy dosage to reduce the adverse event while maintaining its efficacy.