Impact of obesity on prostatectomy outcomes: Insights from a large prospectively maintained cohort

Background: In this study we aimed to explore the impact of BMI on perioperative complications, functional outcomes, and oncologic outcomes and longitudinal outcomes. Methods: We queried our prospectively maintained radical prostatectomy (RP) registry from 1986 to 2018 for patients with cM0 prostate adenocarcinoma without prior BPH surgery or radiation therapy. Preoperative BMI was associated with the following outcomes of interest: 30-day complications, 1-year functional outcomes, and oncologic outcomes. Logistic regression analyses were used for complications and surgical outcomes and competing risk Cox proportional hazard models were used for oncologic outcomes. Results: In a cohort of 21,604 patients, 28.9% and 1.0% had BMI > 30 (N = 6,252) and BMI > 40 (N = 222), respectively. Obese patients were more likely to have positive surgical margins (29.4% vs. 25.0%, P < 0.001) and early complications (15.0% vs. 11.1%, P < 0.001) and these were confirmed on multivariable analysis: OR 1.04 (P < 0.001) and OR 1.04 (P < 0.001), respectively. RP on obese patients also had increased operative times and blood loss. Increasing BMI was associated with lower odds for recovering potency (OR 0.95, P < 0.001) but was not associated with lower rates of postoperative continence (OR 1.005, P = 0.403). On multivariable competing risk analysis, patients with BMI > 30 had higher odds of nonprostate cancer mortality but no difference in biochemical failure, metastasis or cancer-specific survival. Conclusions: RP in obese patients can be technically challenging but delivers similar oncologic outcomes to nonobese patients. This information can be useful for patient counseling to support the use of radical prostatectomy in appropriately selected obese patients.