5580 Background: Obesity and metabolic syndrome (MS) is prevalent in our society, and have been linked to a higher incidence of prostate cancer (PCa). The relationship of obesity or MS and cancer control has yielded mixed results in previous studies. We examined the correlation between the incidence of biochemical recurrence (BCR) with MS and BMI in a cohort of patients with PCa who underwent robotic-assisted laparoscopic prostatectomy (RALP). Methods: A retrospective study of patients who underwent RALP at a single center from 2007 to 2015 was conducted. Parameters including preoperative BMI, fasting glucose, lipid profile, blood pressure, PSA, Gleason score, pathologic stage, time to BCR, and surgical margin status were analyzed. Patients were categorized in high (HR), intermediate (IR), and low-risk (LR) groups based on the National Comprehensive Cancer Network (NCCN) guidelines. WHO classification was used for MS criteria, and BCR was defined as two consecutive postoperative PSA volume of ≥ 0.2 ng/mL. Obesity is defined as BMI ≥30 kg/m2. Results: A total of 726 patients with 189 in HR, 471 in IR and 66 patients in LR groups were included in this study with the median age of 59 (interquartile range [IQR] 55-64) years old. The median follow-up from surgery was 38 (IQR 22-46) months. More obese patients were found in the HR group compared to IR/LR group (46.5% vs. 33.1%, p<0.01). There were also more patients with MS in the HR group compared to IR/LR group (36.5% vs. 12.0%, p<0.01). Obese patients had a higher rate of BCR across risk groups in comparison to non-obese patients 32.1% vs. 15.4% (P<0.001), specifically 68% vs. 40%(p<0.01) in HR group and 21.3% vs. 12.7% (p=0.035) in the IR group. Similarly, patients with MS had a higher rate of BCR in HR and IR groups in comparison to the patients without MS, 39.1% vs. 18.7% (P<0.01); specifically, 67.7% vs. 42.2% (p<0.01) in HR and 29% vs. 11.6% (p<0.01) in the IR group. No correlation between MS or obesity and BCR was observed in LR group. There was no statistically significant difference in the positive surgical margin rate between obese and non-obese cohorts in each risk group. Conclusions: Among HR and IR-PCa patietns who underwent RALP, both obesity and MS correlate with increased risk of BCR. There were significantly more obesity and MS in HR-PCa patients, suggesting a potential pathophysiologic interplay between obesity or MS and cancer progression.
Impact of positive surgical margin on biochemical recurrence in localized prostate cancer
