Impact of body mass index on robot-assisted radical cystectomy with intracorporeal urinary diversion.

OBJECTIVES: To determine the impact of body mass index (BMI) on peri-operative and oncological outcomes after robot-assisted radical cystectomy (RARC) with intracorporeal urinary diversion.

PATIENTS AND METHODS: A total of 216 patients undergoing RARC, extended lymphadenectomy and intracorporeal urinary diversion, between July 2010 and December 2015, were categorized into four BMI groups according to the 2004 World Health Organization obesity classification groups: <25 kg/m2 (normal); 25-29.9 kg/m2 (pre-obese); 30-34.9 kg/m2 (obese class I); and ≥35 kg/m2 (obese class II). Pre-, intra- and postoperative characteristics, oncological outcomes, and 90-day complications were compared using sas statistical software.

RESULTS: All 216 patients underwent intracorporeal urinary diversion, with 68 (32%) undergoing orthotopic neobladder construction. Demographics were similar among the BMI groups with regard to median (range) age (71.8 [35- 95] years), gender (80.6% men), Charlson comorbidity index (CCI) score (66.2% with CCI score 0-1), pathological stage (carcinoma in situ to T2: 55.1%, T3-T4/N0: 18.5%, Tx/N+: 26.4%), median (interquartile range) node count [41 (28, 53)] and positive soft tissue margin rate (4.2%). Obese patients had greater blood loss and longer operating time (P = 0.02 and P = 0.04, respectively). There were no significant differences in length of hospital stay, transfusion rates, readmission or 90-day overall and high-grade complication rates (P = 0.16, P = 0.96, P = 0.89, P = 0.22 and P = 0.51, respectively). At a median (range) follow-up of 13 months (15 days to 4.8 years), recurrence-free survival (P = 0.92) and overall survival (P = 0.68) were similar among the groups.

CONCLUSION: The results of the present study show that RARC with intracorporeal urinary diversion is safe and feasible in obese patients with bladder cancer. BMI was not associated with significant differences in peri-operative, pathological or early oncological outcomes.