Impact of body mass index on clinicopathological outcome and biochemical recurrence after radical prostatectomy

Abstract

BACKGROUND: Accumulating evidence suggests that obesity is associated with tumor progression in prostate cancer (PCa) patients after radical prostatectomy (RP). We conducted a retrospective multicenter study to determine the effect of body mass index (BMI) on the clinicopathological characteristics and biochemical recurrence of PCa in Japanese men who underwent RP. METHODS: The medical records of 1257 men with PCa treated by RP without neoadjuvant therapy at four medical institutes between 2001 and 2009 were retrospectively reviewed. Patients were categorized into four groups using the World Health Organization (WHO) BMI classification and BMI quartiles. Associations of the various BMI categories with clinicopathological characteristics and biochemical recurrences were statistically evaluated. Biochemical recurrence was defined as a PSA level of 40.2 ng ml -1 . RESULTS: Of the 1257 patients, 230 (18.3%) experienced biochemical recurrence during the median follow-up period of 49 months. The median BMI was 23.8 kg m -2 , and 1.4% patients were underweight, 65.4% were of normal weight, 30.9% were overweight and 2.4% were obese (WHO classification). Preoperative PSA levels and PSA density (PSAD) tended to decrease as BMI increased. Pathological characteristics did not differ significantly among BMI categories. As per the WHO classification and quartile categories, biochemical recurrence rate was comparable among the BMI groups. After adjusting for other pre-and postoperative covariables, multivariate Cox proportional hazards analysis revealed that a high BMI did not have an independent impact on biochemical recurrence-free survival. CONCLUSIONS: Underweight Japanese PCa patients treated by RP had higher preoperative PSA levels and PSAD. High BMI was not associated with adverse pathological findings or increased biochemical recurrence rate in Japanese PCa patients treated with RP. Racial differences may exist in the relationship between obesity and outcomes of RP in PCa patients.

Body mass index as a classifier to predict biochemical recurrence after radical prostatectomy in patients with lower prostate-specific antigen levels

“…In Asian patients, the adverse pathological findings of PCa may be attributable to obesity according to previous reports (18,19). However, other reports have not demonstrated any association of obesity with the clinicopathological characteristics of PCa (20,21). Such conflicting results may be explained by the different distribution of BMI among countries.…”

“…Although obesity in Asian countries is less severe compared with that in western countries, certain studies have suggested an association between BMI and PCa, including pathological characteristics (18,19). However, the effect of obesity on PCa-related mortality has been controversial, and it remains unclear whether obesity contributes to the aggressiveness of PCa in Asian patients (20,21). The aim of the present study was to investigate the association between BMI and the clinicopathological characteristics of PCa, and determine whether obesity increases the risk of biochemical recurrence after radical prostatectomy (RP) in Japanese patients.…”

Higher Body Mass Index Increases the Risk for Biopsy-Mediated Detection of Prostate Cancer in Chinese Men

“…In the past few decades, most Asian countries have experienced a boom in the incidence and mortality rate of PCa [ 7 ], which has been generally attributed to a Westernised life style, elevated body weight and increased prostate biopsy rates in Asian populations. Meanwhile, previous studies in Asian populations have drawn contradictory conclusions that BMI had positive, null or negative impacts on the risks of PCa and HGPCa [ 8 – 11 ]. Recently, Masuda et al reported higher rates of PCa and HGPCa detection in patients with a BMI <21 kg/m 2 compared to those with a BMI from 21–22.9 kg/m 2 in Japanese men [ 12 ].…”

Reassessment of the risk factors for biochemical recurrence in D'Amico intermediate‐risk prostate cancer treated using radical prostatectomy

“…We previously established a multicenter retrospective database of PCa patients who received radical prostatectomy at four institutions in the Tohoku district of Japan to assess the outcome and problems associated with radical surgery without any neoadjuvant treatments for localized PCa . Here, we investigated the effects of various clinical and pathological factors on BCR‐free survival in D'Amico intermediate‐risk patients, and tried to re‐stratify patients with intermediate‐risk PCa into two groups according to BCR, after radical prostatectomy, using our multicenter database.…”