Neoadjuvant chemoradiation therapy for resectable esophago-gastric adenocarcinoma: a meta-analysis of randomized clinical trials

Background The efficacy and safety of preoperative chemoradiation therapy (CRT) for advanced esophago-gastric adenocarcinoma are still in question, and the prognosis of these patients is poor. Methods We systematically searched electronic databases from January 1990 to July 2014. The primary outcome was overall survival. The secondary outcomes were a R0 resection rate, positive rate of lymph node metastasis, postoperative recurrence rate, pathological complete response (pCR) rate and perioperative mortality. Overall survival was measured with a hazard ratio (HR), while other secondary outcomes were measured with an odds ratio (OR). Results Seven randomized controlled trials (RCTs) including 1085 patients were searched and, of these, 869 had adenocarcinoma. Patients receiving preoperative CRT had a longer overall survival (HR 0.74; 95% confidence interval (CI) 0.63–0.88), higher likelihood of R0 resection and greater chance of pCR, while they had a lower likelihood of lymph node metastasis and postoperative recurrence. The difference of perioperative mortality was non-significant. In addition, the result of the comparison between preoperative CRT and preoperative chemotherapy (CT) in two RCTs was non-significant. Conclusion Patients with resectable esophago-gastric adenocarcinoma can gain a survival advantage from preoperative CRT. However, limited to the number of RCTs, the effect of adding radiotherapy to preoperative CT separately is still uncertain and more high-quality prospective trials are needed.