AIM: To evaluate the perioperative and long term outcomes of cystectomy in obese patients.METHODS: This is a retrospective review of 580 patients for whom radical cystectomy(RC) was performed for primary urothelial bladder cancer between November 1996-April 2013 at a single institution. Body mass index(BMI) was available for 424 patients who were categorized as underweight(< 18.5), normal(18.5-24.9), overweight(25.0-29.9), and obese(≥ 30). Baseline demographics, perioperative outcomes, and survival were assessed. Overall survival(OS) and disease specific survival(DSS) was estimated by Kaplan-Meier method. Medians were compared using the Mann-Whitney U Test. Categorical variables were compared using the χ2 test. A P-value of < 0.05 was considered statistically significant. Statistical analyses were performed using the Software Package for the Social Sciences(SPSS), Version 20(International Business Machines SPSS, Chicago, IL, United States). RESULTS: The median age of all patients was 69 years(inter-quartile range 60-75) and median followup was 23.4 mo(8.7-55.1). Patients were characterized as underweight [9,(2.1%)], normal [113,(26.7%)],overweight [160,(37.8%)], or obese [142,(33.5%)]. Estimated blood loss during RC was higher in the obese group(800 m L) as compared to the normal weight group(500 m L). However, need for transfusion(47.7% vs 52.1%), number of lymph nodes resected(32 vs 30), length of stay(9 d vs 8 d), and 30-d readmission(29.7% vs 25.2%) between obese and normal BMI patients were similar. Obese patients underwent ileal neobladder diversion in 42% of cases, compared to 24% of normal BMI patients(0.003). Normal BMI and obese patients had comparable urinary incontinence(21.4% vs 25.6%, P = 0.343), and need for intermittent catheterization(14.3% vs 5.2%, P = 0.685) at 2 years follow-up. Overall survival was better in obese compared to normal BMI patients on univariate analysis, with median survival of 67 mo vs 37 mo, respectively(P = 0.031). Disease specific survival in these populations followed the same Kaplan Meier curve, with the obese group having a significantly improved OS, P = 0.016. Underweight patients had a significantly worse prognosis, with a median overall survival of 19 mo(P = 0.018). Disease specific survival was significantly worse in the underweight group compared to the obese group, P = 0.007. On multivariate analysis underweight patients remained at increased risk for death(HR = 3.1, P = 0.006), as were older patients(HR = 1.6, P = 0.006), those with multiple nodal metastases(HR = 3.7, P = 0.007), and those who had received neoadjuvant chemotherapy(HR = 2.0, P = 0.015).CONCLUSION: Perioperative outcomes and survival following RC in obese patients is comparable with nonobese patients. Underweight patients have the worst OS and DSS. AIM: To evaluate the perioperative and long term outcomes of cystectomy in obese patients. METHHODS: This is a retrospective review of 580 patients for whom radical cystectomy (RC) was performed for primary urothelial bladder cancer between November 1996-April 2013 at a single institution Body mass index (BMI) was available for 424 patients who were categorized as underweight (<18.5), normal (18.5-24.9), overweight (25.0-29.9), and obese (≥ 30). Baseline demographics, perioperative outcomes, and Overall survival (OS) and disease specific survival (DSS) was estimated by Kaplan-Meier method. Medians were compared using the Mann-Whitney U Test. Categorical variables were compared using the χ2 test. A P-value of < Statistical was performed using the Software Package for the Social Sciences (SPSS), Version 20 (International Business Machines SPSS, Chicago, IL, United States). RESULTS: The median age of all patients wa Patients were characterized as underweight [9, (2.1%)], normal [113, (26.7%)], overweight [ 160, 37.8%], or obese [142, (33.5%)]. Estimated blood loss during RC was higher in the obese group (800 m L) as compared to the normal weight group need for transfusion (47.7% vs 52.1%), number of lymph nodes resected (32 vs 30), length of stay (9d vs 8d), and 30-d readmission Obese patients underwent ileal neobladder diversion in 42% of cases, compared to 24% of normal BMI patients (0.003). Normal BMI and obese patients had comparable urinary incontinence (21.4% vs 25.6%, P = 0.343), and need for intermittent catheterization (14.3% vs 5.2%, P = 0.685) at 2 years follow-up. Overall survival was better in obese compared to normal BMI patients on univariate analysis, with median survival of 67 mo vs 37 mo, respectively (P = 0.031). Disease s pecific survival in these populations followed the same Kaplan Meier curve, with the obese group having a significantly improved OS, P = 0.016. Underweight patients had a potential worse prognosis, with a median overall survival of 19 mo (P = 0.018). survival was significantly worse in the underweight group compared to the obese group, P = 0.007. On multivariate analysis underweight patients remained at increased risk for death (HR = 3.1, P = 0.006), as were older patients (HR = 0.006), those with multiple nodal metastases (HR = 3.7, P = 0.007), and those who had neoadjuvant chemotherapy (HR = 2.0, P = 0.015) .CONCLUSION: Perioperative outcomes and survival following the RC in obese patients is comparable with nonobese patients. Underweight patients have the worst OS and DSS.