Effects of specific nutrients on immune modulation in patients with gastrectomy

Gastric cancer (GC) is one of the most prevalent and lethal malignant neoplasms worldwide. The main treatment for GC is gastrectomy, which generally causes considerable metabolic stress to patients. To modulate cell function, maintain homeostasis of the immune response, reduce postoperative complications, and obtain favorable outcomes, physicians prescribe specific nutrients with immunomodulatory properties as supplementation to enteral or parenteral formulas, indicating immunonutrition. In the formulas, among the immunonutrients, glutamine, arginine, and n-3 polyunsaturated fatty acids are the most commonly used either alone or in combination. The present review summarizes and focuses on the evidence obtained from clinical trials and animal studies supporting the role of immunonutrients supplemented enterally or parenterally in total or subtotal gastrectomy. In addition, this review describes the possible molecular mechanisms underlying the protective action of these immunonutrients, which may contribute to therapeutic approaches to improve postoperative outcomes of gastrectomy. Combination of conventional therapy with immunonutrition seems to be a useful strategy to achieve synergistic effects in the treatment of GC patients.