Effects of Preoperative Immunonutrition on Postoperative Complications in Patients Undergoing Colorectal Cancer...

Surgical resection, the primary treatment for colorectal cancer (CRC), often leads to postoperative complications affecting quality of life. Immunonutrition (IN), in the near-surgical setting, may be an effective strategy for enhancing the postoperative course.

To explore the effect of IN formulas during the perioperative course on infectious and noninfectious, postsurgical complications and length of hospital stay (LOS).

A search of the literature was performed in Web of Science and Scopus, combining the terms "Colorectal Cancer," "Immunonutrition," and "Postoperative Complications." The search was conducted for studies published between January 2017 and June 2023, with no restrictions on language.

The primary outcomes were infectious/noninfectious complications and LOS. Secondary outcomes were markers of immune function and inflammatory response. Of 1018 studies identified, 10 met the eligibility criteria: 50% were randomized controlled trials and the rest were prospective randomized trials. Three studies assessed preoperative and 7 assessed perioperative IN administration. Using individual substrates, 2 studies administered omega-3 fatty acids, 1 administered glutamine, and 1 administered arginine. Finally, using a combination of substrates, 4 studies used omega-3, arginine, and nucleotides, while 2 used omega-3 and arginine. The meta-analyses revealed significant reductions in minor infectious complications (risk ratio [RR], 0.67; 95% CI, 0.51 to 0.89; P < .01), whereas no effect was observed for general infectious complications (RR, 0.71; 95% CI, 0.48 to 1.05; P = .09), noninfectious complications (RR, 1.02; 95% CI, 0.71 to 1.46; P = 0.92), or LOS (RR, 0.09; 95% CI, -0.19 to 0.37; P = 0.53). Participants and intervention characteristics were analyzed as potential moderators, with higher IN doses consistently linked to greater reductions in infection risk, highlighting dose as a key moderator.

This meta-analysis revealed significant reductions in minor infectious complications in patients undergoing CRC resection. However, methodological variability and the small number of studies made it challenging to draw clear conclusions.

PROSPERO no. CRD42024515921.