PURPOSE: Obesity is a modifiable risk factor associated with worse outcomes for many cancers, yet implications for prostate cancer are not well understood.
Notably, the impact of body mass index (BMI) on long-term survival following treatment is unclear. We performed a retrospective cohort study on a large series of men who underwent radical prostatectomy (RP) to assess the impact of obesity on long-term biochemical recurrence-free survival (BRFS), prostate cancer-specific survival (PCSS) and overall survival (OS).
MATERIALS AND METHODS: Between 1982 and 2012, 11,152 men underwent RP at a single tertiary referral center. Patients were stratified according to BMI: 1) normal weight (BMI< 25) 2) overweight (25 ≥ BMI< 30) 3) mild obesity (30 ≥ BMI< 35) and 4) moderate/severe obesity (BMI ≥ 35), comprising 27.6%, 56.0%, 14.1%, and 2.3% of the cohort, respectively. Covariates included age, preoperative PSA, surgery year, Gleason score, pathologic stage, surgical margin and race. Predictors of BRFS, PCSS, and OS were identified using Cox proportional hazard models.
RESULTS: The median (range) follow-up was 5 (1-27) years. Actuarial 20-year BRFS for mild and moderate/severe obesity were 65% and 51%, respectively, compared to 76% for normal weight men (p≤ 0.001). In a multivariable model, obesity was a significant predictor of BRFS (mild HR:1.30,p=0.002; moderate/severe HR:1.45;p=0.028) and OS (mild HR:1.41,p=0.003; moderate/severe HR:1.81,p=0.033), but only mild obesity was significantly associated with PCSS (HR:1.51,p=0.040) whereas moderate/severe obesity was not (HR:1.58,p=0.356).
CONCLUSIONS: Obese men have higher rates of biochemical recurrence than normal-weight patients over long-term follow up. Obesity at the time of surgery independently predicts OS and BRFS, but not PCSS.
Written by:
Chalfin HJ, Lee SB, Jeong BC, Freedland SJ, Feng Z, Trock BJ, Partin AW, Humphreys E, Walsh PC, Han M. Are you the author?
Reference: J Urol. 2014 Apr 21. pii: S0022-5347(14)03421-1.
doi: 10.1016/j.juro.2014.04.086
PubMed Abstract
PMID: 24769031
UroToday.com Prostate Cancer Section