Impact of Perioperative Immunonutrition on Postoperative Outcomes for Patients Undergoing Head and Neck or Gastrointestinal Cancer Surgeries: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

Objective: To clarify whether perioperative immunonutrition is effective in adult patients with or without malnutrition undergoing elective surgery for head and neck (HAN) or gastrointestinal (GI) cancers. Background: It is important to avoid postoperative complications in patients with cancer as they can compromise clinical outcomes. There is no consensus on the efficacy of perioperative immunonutrition in patients with or without malnutrition undergoing HAN or GI cancer surgery. Materials and Methods: We searched MEDLINE (PubMed), MEDLINE (OVID), EMBASE, Cochrane Central Register of Controlled Trials, Web of Science Core Selection, and Emcare from 1981 to 2022 using search terms related to immunonutrition and HAN or GI cancer. We included randomized controlled trials. Intervention was defined as immunonutritional therapy including arginine, n-3 omega fatty acids, or glutamine during the perioperative period. The control was defined as standard nutritional therapy. The primary outcomes were total postoperative and infectious complications, defined as events with a Clavien--Dindo classification grade ≥ II that occurred within 30 days after surgery. Results: Of the 4825 patients from 48 included studies, 19 had upper GI cancer, 9 had lower, and 8 had mixed cancer, whereas 12 had HAN cancers. Immunonutrition reduced the total postoperative complications (relative risk ratio: 0.78; 95% CI, 0.66-0.93; certainty of evidence: high) and infectious complications (relative risk ratio: 0.71; 95% CI, 0.61-0.82; certainty of evidence: high) compared with standard nutritional therapy. Conclusions: Nutritional intervention with perioperative immunonutrition in patients with HAN and GI cancers significantly reduced total postoperative complications and infectious complications. [ABSTRACT FROM AUTHOR]