The impact of radiotherapy on survival in resectable gastric carcinoma:: A meta-analysis of literature data

Background: The benefit of external radiotherapy for gastric carcinoma has been extensively studied, but data on survival are still equivocal. Objective: To assess the effectiveness of surgery combined with preoperative radiotherapy or postoperative chemoradiotherapy in the reduction of all-cause mortality in patients with resectable gastric carcinoma. Methods: Computerised bibliographic searches of MEDLINE and CANCERLIT (1970-2006) were supplemented with hand searches of reference lists. Study selection: Studies were included if they were randomised controlled trials (RCTs) comparing mortality of surgery combined with preoperative radiotherapy or postoperative chemoradiotherapy to surgery alone, and if they included patients with histologically-proven gastric adenocarcinoma without metastases. Nine eligible RCTs, 4 of preoperative radiotherapy (832 patients) and 5 of postoperative chemoradiotherapy (869 patients), were identified and included in the meta-analysis. Data extraction: Data on study populations, interventions, and outcomes were extracted from each RCT according to the intention to treat method by three independent observers and combined using the DerSimonian and Laird method. Results: Surgery combined with preoperative radiotherapy compared to surgery atone significantly reduced the 3-year (OR 0.57; 95% Cl 0.43-0.76: p = 0.0001) and 5-year (OR 0.62; 95% Cl 0.46-0.84; p = 0.002) mortality rate. A significant reduction of the 5-year (OR 0.45; 95% Cl 0.32-0.64; p < 0.00001) mortality rate was observed when surgery followed by chemoradiotherapy was compared to surgery atone. Conclusions: In patients with resectable gastric carcinoma, adjuvant radiotherapy significantly reduces 3-year and 5-year all-cause mortality, but the magnitude of the benefit is relatively small. Available evidence is inadequate to determine whether postoperative chemoradiotherapy is superior to preoperative radiotherapy. (c) 2007 Elsevier Ltd. All rights reserved.