Systematic review on immunonutrition in partial pancreatoduodenectomy

Background: The effect of immunonutrition (IM) on postoperative outcomes has been investigated in gastrointestinal cancer surgery; however, strong evidence regarding IM in partial pancreatoduodenectomy (PD) is lacking. This study evaluated the effect of IM on short-term outcomes in patients undergoing PD. Methods: A systematic literature review of randomized controlled trials was conducted to identify the studies investigating the IM effect on outcomes in PD. Random-effects meta-analyses were conducted to calculate the pooled risk ratio (RR). Studies were evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. Results: Five studies were included in the meta-analysis. IM was associated with a lower incidence of overall complications (RR 0.74; 95% confidence interval (CI) 0.58, 0.94; P = 0.01; I² = 0%) and infectious complications (RR 0.60; 95% CI 0.42, 0.84; P = 0.003; I² = 0%). However, no significant association was noted in the incidence of major complications (RR 0.68; 95% CI 0.41, 1.12; P = 0.13), mortality (RR 0.79; 95% CI 0.16, 3.99; P = 0.78), postoperative pancreatic fistula (RR 0.92, 95% CI 0.59, 1.46; P = 0.74), and delayed gastric emptying (RR 1.09; 95% CI 0.55, 2.15; P = 0.81). Conclusions: IM administration in PD can prevent the incidence of overall and infectious complications postoperatively (GRADE recommendation: moderate). However, IM has no impact on major complications, mortality, and PD-specific complications (GRADE recommendation: low).