Perioperative immunonutrition in gastric cancer patients can reduce perioperative morbidity and may improve quality of their life. Patients with gastric cancer will be divided into four groups depending on the type of artificial nutrition. Group I (enteral feeding) and II (enteral feeding and parenteral nutrition with glutamine) will be administered nutritional therapy during the postoperative period, group III (oral arginine) and IV (parenteral immunonurition) patients will be treated nutritionally both prior to and after the surgery. The lymphocytes and their subpopulations, interleukin IL-1B,-6,-23, and the phagocytic, and bactericidal activity of blood platelets will be determined before and after nutritional therapy.