title: Body mass index is not a predictor of biochemical recurrence after radical prostatectomy in Dutch men diagnosed with prostate cancer.
abstract: OBJECTIVE
  To determine the effect 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 identified 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/m(2)), overweight (BMI 25-30 kg/m(2)), or obese (BMI ≥ 30 kg/m(2)). 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 significantly differ among BMI groups. Pathological characteristics after radical prostatectomy did not significantly differ 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% Confidence 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/m(2), 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 finding is unclear, because BMI was not an independent predictor of biochemical recurrence after radical prostatectomy.
authors.affiliation: Department of Urology, Radboud University Nijmegen Medical Centre, PO Box 9101, 6500 HB Nijmegen, The Netherlands.
authors.forename: Dieuwertje E G
authors.initials: DE
authors.lastname: Kok
authors.forename: Joep G H
authors.initials: JG
authors.lastname: van Roermund
authors.forename: Katja K
authors.initials: KK
authors.lastname: Aben
authors.forename: Moniek W M
authors.initials: MW
authors.lastname: van de Luijtgaarden
authors.forename: Herbert F M
authors.initials: HF
authors.lastname: Karthaus
authors.forename: Oncko B
authors.initials: OB
authors.lastname: van Vierssen Trip
authors.forename: Ellen
authors.initials: E
authors.lastname: Kampman
authors.forename: J
authors.initials: J
authors.lastname: Alfred Witjes
authors.forename: Lambertus A L M
authors.initials: LA
authors.lastname: Kiemeney
mesh_terms: D000368:Aged; D015992:Body Mass Index; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000097:blood / Q000453:epidemiology*; D009426:Netherlands; D011379:Prognosis; D011468:Prostatectomy / Q000379:methods; D011471:Prostatic Neoplasms / Q000097:blood / Q000453:epidemiology* / Q000601:surgery*; D012189:Retrospective Studies