Body mass index is not a predictor of biochemical recurrence after radical prostatectomy in Dutch men diagnosed with prostate cancer

Purpose To determine the eVect of body mass index (BMI) on clinical and pathological characteristics at time of diagnosis and on risk of biochemical recurrence after radical prostatectomy among Dutch men diagnosed with prostate cancer. Methods In total, 1,116 prostate cancer patients with known BMI, diagnosed between 2003 and 2006, were identiWed from the population-based cancer registry held by the Comprehensive Cancer Centre East, The Netherlands. Of these, 504 patients underwent a radical prostatectomy. Patients were categorized as normal weight (BMI <25 kg/m2), overweight (BMI 25–30 kg/m2), or obese (BMI ¸ 30 kg/m2). Multivariable proportional hazards regression models, adjusted for age, prediagnostic PSA levels, and pathological characteristics were used to evaluate BMI as a prognostic factor for biochemical recurrence after radical prostatectomy. Results Overall, clinical and biopsy characteristics did not signiWcantly diVer among BMI groups. Pathological characteristics after radical prostatectomy did not signiWcantly diVer among BMI groups, except for tumor stage, which was highest in obese patients (P = 0.017). For patients treated with radical prostatectomy, 5-year risk (95% ConWdence Intervals) of biochemical recurrence was 30% (23– 37%) for normal weight, 32% (25–39%) for overweight, and 25% (9–41%) for obese patients (log rank P = 0.810). BMI was not an independent prognostic factor for biochemical recurrence in multivariable proportional hazards regression analyses (HR 0.99 per kg/m2, 95% CI: 0.93–1.06). Conclusions Compared with non-obese men, pathological tumor stage tended to be higher in obese men. Clinical relevance of this Wnding is unclear, because BMI was not an independent predictor of biochemical recurrence after radical prostatectomy