Immunonutrition vs Standard Nutrition for Cancer Patients: A Systematic Review and Meta-Analysis (Part 1)

The aim of this study was to determine the efficacy of immunonutrition vs standard nutrition in cancer patients treated with surgery. Cochrane Central Register of Controlled Trials, EMBASE, MEDLINE, EBSCOhost, and Web of Science were searched. Sixty-one randomized controlled trials were included. Immunonutrition was associated with a significantly reduced risk of postoperative infectious complications (risk ratio [RR] 0.71 [95% CI, 0.64-0.79]), including a reduced risk of wound infection (RR 0.72 [95% CI, 0.60-0.87]), respiratory tract infection (RR 0.70 [95% CI, 0.59-0.84]), and urinary tract infection (RR 0.69 [95% CI, 0.51-0.94]) as well as a decreased risk of anastomotic leakage (RR 0.70 [95% CI, 0.53-0.91]) and a reduced hospital stay (MD -2.12 days [95% CI -2.72 to -1.52]). No differences were found between the 2 groups with regard to sepsis or all-cause mortality. Subgroup analyses revealed that receiving arginine + nucleotides + ω-3 fatty acids and receiving enteral immunonutrition reduced the rates of wound infection and respiratory tract infection. The application of immunonutrition at 25-30 kcal/kg/d for 5-7 days reduced the rate of respiratory tract infection. Perioperative immunonutrition reduced the rate of wound infection. For malnourished patients, immunonutrition shortened the hospitalization time. Therefore, immunonutrition reduces postoperative infection complications and shortens hospital stays but does not reduce all-cause mortality. Patients who are malnourished before surgery who receive arginine + nucleotides + ω-3 fatty acids (25-30 kcal/kg/d) via the gastrointestinal tract during the perioperative period (5-7 days) may show better clinical efficacy.