Published online Mar 24, 2016. doi: 10.5410/wjcu.v5.i1.53
Peer-review started: August 31, 2015
First decision: October 8, 2015
Revised: October 30, 2015
Accepted: February 14, 2016
Article in press: February 16, 2016
Published online: March 24, 2016
Processing time: 202 Days and 17.6 Hours
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 follow-up 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 mL) as compared to the normal weight group (500 mL). 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 non-obese patients. Underweight patients have the worst OS and DSS.
Core tip: As obesity rates increase, more obese patients will require radical cystectomy for muscle invasive bladder cancer. Anecdotally, obesity increases the technical difficulty of an operation. Literature regarding outcomes of obese patients undergoing radical cystectomy is limited. This study shows obese patients do better than their non-obese counterparts in terms of perioperative outcomes and overall and disease specific survival. However, we found that underweight patients have a significantly decreased overall and disease specific survival compared with obese and patients.