Body mass index is associated with higher Gleason score and biochemical recurrence risk following radical prostatectomy in Chinese men: a retrospective cohort study and meta-analysis

BACKGROUND: The aim of the study is to investigate whether body mass index (BMI) affected pathological characteristics and biochemical recurrence (BCR) of prostate cancer after radical prostatectomy in Chinese men. METHODS: Medical records of 211 Chinese patients who underwent radical prostatectomy between 2006 and 2014 were retrospectively reviewed, with follow-up time of 24.5 ± 27.0 months. Multivariate logistic and Cox regression analyses were applied to address the impact of BMI on adverse pathological outcomes and BCR following prostatectomy. A meta-analysis of published studies from MEDLINE or EMBASE was conducted to determine the relationship between BMI and BCR following prostatectomy among Asian populations. RESULTS: Higher BMI was positively correlated with higher biopsy Gleason score (odds ratios (OR) 1.163, 95 % confidence interval (CI) 1.023–1.322, P = 0.021) and pathological Gleason score (OR 1.220, 95 % CI 1.056–1.410, P = 0.007) in multivariate analysis. BCR was detected in 48 patients (22.7 %). Multivariate Cox proportional hazards analysis revealed that higher BMI (hazard ratio (HR) 1.145, 95 % CI 1.029–1.273, P = 0.013) and prostate-specific antigen (HR 1.659, 95 % CI 1.102–2.497, P = 0.015) levels were independent predictors of BCR. The meta-analysis enrolled eight Asian studies of 4145 patients treated by radical prostatectomy. Based on random-effects approach, a 5 kg/m(2) increase in BMI was correlated with 28 % higher risk of BCR (HR 1.22, 95 % CI 0.86–1.72) without statistical significance. CONCLUSIONS: The present study suggested that higher BMI was an independent risk factor for a higher Gleason score, as well as an independent predictor of BCR after radical prostatectomy in Chinese patients. Meta-analysis of Asian studies also indicated that obese patients, although without statistical significance, might be more likely to suffer from BCR.