Safety and efficacy of preoperative chemoradiotherapy versus chemotherapy for resectable gastric cancer: A systematic review and meta-analysis.

Abstract

e16105 Background: Gastric cancer (GC), being the 5th most prevalent malignancy globally and 3rd leading cause of cancer related mortality, has an overall 5-year survival rate of 20-30%. Recently, preoperative chemoradiotherapy has emerged as a potentially curative approach to enhance the prognosis of patients with GC, as opposed to surgery alone. The aim of this study was to evaluate the safety and efficacy of preoperative chemoradiotherapy versus preoperative chemotherapy for resectable GC. Methods: A comprehensive search was conducted using PubMed, Cochrane, Clinicaltrials.gov, Embase, and Scopus databases from inception to December 24th, 2024. Studies that compared preoperative chemoradiotherapy (CRT) in comparison to preoperative chemotherapy in patients with resectable gastric cancer were aggregated. Data on treatment completed rate, distant and locoregional metastasis, gastrointestinal side effects, neutropenia, and hematological side effects were extracted and analyzed. Meta-analysis was performed using RevMan version 5.4.1. The outcomes were pooled as odds ratio (OR) with 95% confidence intervals (CI) using the random effects model. The interstudy heterogeneity was assessed using Higgins I2 statistics. Results: Our research comprises thirty studies with a total of 20,914 patients. In comparison to chemotherapy alone, preoperative chemoradiotherapy (CRT) was associated with a significant increase in overall neutropenia (OR: 1.57[1.32, 1.86]; 95% CI, I2 = 0%, p < 0.00001) and gastrointestinal side effects (OR: 1.33[1.04, 1.71]; 95% CI, I2 = 0%, p = 0.02) in addition to decreased locoregional metastasis (OR: 0.63[0.48, 0.84]; 95% CI, I2 = 57%, p = 0.001). However, no significant effect was observed in nausea and vomiting (OR: 1.08[0.68, 1.72]; 95% CI, I2 = 62%, p = 0.75), treatment completed rate (OR: 0.78[0.58, 1.06]; 95% CI, I2 = 62%, p = 0.12), distant metastasis (OR: 0.90[0.77, 1.04]; 95% CI, I2 = 0%, p = 0.15) and hematological side effects (OR: 1.28[0.82, 2.02]; 95% CI, I2 = 62%, p = 0.28). Conclusions: This meta-analysis demonstrates that preoperative chemoradiotherapy (CRT) significantly increases the risk of overall neutropenia and gastrointestinal side effects compared to chemotherapy alone. Additionally, CRT is associated with a notable reduction in locoregional metastasis, underscoring its potential as an effective preoperative intervention to improve local disease control. However, CRT showed no significant impact on nausea and vomiting, treatment completion rates, distant metastasis, or hematological side effects.