Does enteral immune nutrition (EIN) boost the immunity of gastric cancer (GC) patients undergoing surgery? A systematic review and meta-analysis

Introduction
The main components of enteral immunonutrition (EIN) are -3 fatty acids, glutamine, arginine, and nucleotide, which primarily raises the immunity of the host and helps to reduce postoperative infections and non-infectious difficulties. Although the potential benefits of EIN are widely reported, some researchers did not find it to be of much help, and hence valid conclusions about its role are still unclear. Aim: To evaluate the role of enteral immunonutrition on patients undergoing surgery for gastric cancer (GC).

Material and methods
Appropriate articles were searched from the PubMed, Medline, and Central databases using the appropriate keywords as per the PRISMA guidelines. Randomized controlled trials, and retrospective, prospective, and open-label studies were included as per the predefined PICOS criteria. Demographic summary and event data for the effect of EIN on patients undergoing surgery for GC were extracted from the included studies.

Results
Twelve randomized controlled clinical trials with a total of 10,422 gastric cancer patients were included. We found the odds ratio value of 0.23 (95% CI: 0.09–0.59). The results are heterogeneous with a 2 value of 2.77, a 2 value of 1707.96, a df value of 11, an I2 value of 99%, a z value of 3.04, and a p-value of less than 0.05. The risk ratio is 0.47 (95% CI: 0.29–0.77) with heterogeneity of 2 value of 0.73, 2 value of 1428.34, df value of 11, I2 value of 99%, z value of 2.99, and p-value < 0.05.

Conclusions
The present meta-analysis strongly commends the use of EIN to boost the immunity of gastric cancer (GC) patients undergoing gastrectomy.