Increasing Body Mass Index Negatively Impacts Outcomes Following Robotic Radical Prostatectomy

OBJECTIVE: To clarify the impact of increasing body mass index (BMI) on outcomes following robotic radical prostatectomy. METHODS: From January 2003 to May 2005, 132 patients with clinically localized prostate cancer underwent a robotic radical prostatectomy. Patients were divided into 3 cohorts based on BMI: 38 normal (range, 18 to 24.9), 60 overweight (range, 25 to 29.9), and 34 obese (BMI>30). RESULTS: The operative time was significantly longer in obese (304 min) men compared with overweight (235 min) and normal (238 min) BMI patients (P<0.001). Estimated blood loss was significantly greater in both the obese (316 mL) and overweight (318 mL) groups compared with men with normal BMI (234 mL) (P<0.005). Three patients (1 obese and 2 overweight) required conversion to open surgery. Twenty-three of 132 men (17%) had a positive surgical margin, with obese (21%) and overweight (20%) men at a greater risk compared with normal BMI men (11%). No significant differences existed between groups with regard to final pathologic stage, Gleason score, biochemical recurrence at 1-year, and postoperative complication rate. CONCLUSION: Overweight and obese men had a longer operative duration, greater blood loss, longer hospital duration, and higher positive surgical margin rate. Robotic prostatectomy in men with elevated BMI is technically more challenging and is associated with more operative morbidity.