Impact of Preoperative Immunonutrition on Perioperative Outcomes following Cystectomy

Purpose: Radical cystectomy (RC) for the management of muscle-invasive bladder cancer remains a morbid procedure with high rates of perioperative complications. The role of preoperative immunonutritional supplementation (pre-INS) in improving post-RC outcomes is promising and needs further validation. Materials and Methods: We performed a retrospective review of 204 patients who underwent RC for bladder cancer at a single institution, comparing patients who received oral L-arginine-based pre-INS, and those who did not. Preoperative features, postoperative complications, and readmission data were collected. Outcomes of interest included development of high-grade (Clavien-Dindo III-V) complications, readmission within 30 days, ileus, total parenteral nutrition (TPN) requirement, postoperative infection, and length of stay (LOS). Categorical and continuous outcomes were assessed using Fisher's exact test and Welch T-test, respectively. Multivariable logistic regression (MLoR) analysis was used to identify predictive factors for our outcomes. Results: Patients who received pre-INS had significantly lower odds of requiring postoperative TPN (17.3% vs 35.6%; Fisher p=0.015, OR=0.38) and developing postoperative infection (25% vs 45%; Fisher p=0.003; OR=0.41) but no significant difference in the rates of other outcomes. On MLoR, when adjusting for age, gender, body mass index, Charlson comorbidity index, undergoing neoadjuvant chemotherapy and operative features, pre-INS was a significant predictor of postoperative infection (Fisher p=0.02; OR=0.35) but not for high-grade complications, readmission, ileus, needing TPN or LOS. Conclusions: Preoperative immunonutrition with an L-arginine-based supplement is associated with significant reduction in postoperative infection, one of the most common complications of RC.