PURPOSE: To compare the perioperative, functional, and oncological outcomes of the intracorporeal neobladder (ICNB) and extracorporeal neobladder (ECNB) technique following robot-assisted radical cystectomy (RARC). METHODS: We reviewed our single-institutional, prospectively collected database for consecutive patients who underwent RARC with an ileum neobladder from July 2016 to February 2023. Patients were divided into 2 groups according to the approach of reconstruction (ICNB or ECNB). The chi-squared test and Wilcoxon test were used to summarize categorical and continuous variables, respectively. survival and complication outcomes were analyzed using Kaplan-Meier curves, multivariate logistic regression and Cox hazards models. RESULT: Among 304 patients, 190 ICNB patients and 114 ECNB patients were identified. A shorter median operative time (320 vs. 354 min
p = 0.001) and less median EBL (300 vs. 500 ml
p <
0.001) were recorded in the ICNB group. A significant difference in 90-d overall complications was detected between the 2 groups (49.5% vs. 61.4%
p = 0.043). Multivariate logistic regression analysis demonstrated that age, relapsed tumor and surgical approach (ECNB/ICNB) were individual predictive factors for 90-d overall complications. The functional outcomes and survival rates were comparable between the ICNB and ECNB groups. A Cox proportional hazards model indicated that higher pathological stage and pN status are predictors of both recurrence-free survival (RFS) and overall survival (OS). CONCLUSION: Compared with ECNB, ICNB significantly improves perioperative outcomes without compromising functional or oncological outcomes.