Benefit of radiotherapy on survival in resectable gastric carcinoma: a meta-analysis

We aimed to perform a meta-analysis to assess the impact of radiotherapy (RT) on both 3- and 5-year survival in patients with resectable gastric cancer. Relevant studies were identified by using PubMed, Embase and the Cochrane Controlled Trials Register through May 2013. We included randomized clinical trials (RCTs) that compared survival of surgery combined with RT (preoperative and/or postoperative) to surgery alone or surgery plus chemotherapy. Meta-analysis was performed using risk ratios (RRs). Both fixed- and random-effects models were used to calculate the summary risk estimates. Fourteen RCTs involving 2,853 participants were included in this meta-analysis. The addition of RT significantly increased the 3-year (RR 1.19; 95% confidence interval (CI) 1.05-1.35) and 5-year survival (RR 1.25; 95% CI 1.12-1.40). A significant advantage was also observed in subgroup analysis of preoperative RT for both 3-year (RR 1.56; 95% CI 1.19-2.05) and 5-year overall survival (RR 1.40; 95% CI 1.13-1.73). There was no evidence that preoperative RT increased postoperative mortality (RR 0.85; 95% CI 0.42-1.72). Surgery combined with RT or chemoradiotherapy compared to surgery alone improved the 3-year (RR 1.18; 95% CI 1.01-1.38) and 5-year survival rate (RR 1.38; 95% CI 1.18-1.61). Although the quality of the studies was variable, the data were consistent, and no substantial publication bias was observed. In patients with resectable gastric carcinoma, adjuvant RT significantly increased the 3-year and 5-year survival. Preoperative RT is safe and definitely improves overall survival. Available evidence is insufficient to determine the benefit of postoperative RT after an extended lymphadenectomy and radical resection.