Racial differences in adipose tissue distribution and risk of aggressive prostate cancer among men undergoing radiation therapy - Abstract

Background: While elevated body mass index (BMI) has been associated with increased risk of aggressive prostate cancer (PC), the importance of adipose tissue distribution is not well understood.

We examined associations between overall and visceral obesity and aggressive PC risk. Moreover, given racial differences in adipose tissue distribution, we examined whether race modified these associations.

Methods:We conducted a cross-sectional analysis of 308 radiation-treated PC patients within the Durham VA from 2005-2011. Multivariable logistic regression examined the association between BMI categories and tertiles of waist circumference (WC), visceral fat area (VFA) and periprostatic adipose tissue area (PPAT) with high-grade PC risk (Gleason score ≥7 vs. ≤ 6). Models stratified by race examined whether these associations differed between black and non-black men.

Results:Both elevated BMI (p-trend=0.054) and WC (p-trend=0.040) were associated with increased high-grade PC risk, with similar results between races, although the association with BMI was not statistically significant. In contrast, elevated VFA was associated with increased aggressive PC risk in black men (p-trend=0.002) but not non-black men (p-trend=0.831), with a significant interaction between race and VFA (p-interaction=0.035). Though similar patterns were observed for PPAT, none were statistically significant.

Conclusions:Among men undergoing radiation therapy for PC, visceral obesity is associated with increased aggressive PC risk, particularly among black men. If confirmed in future studies, these results suggest adipose tissue distribution differences may contribute to PC racial disparity. Impact:These findings highlight the need to elucidate mechanisms contributing to racial differences in the association between visceral obesity and aggressive PC.

Written by:
Allott EH, Howard LE, Song HJ, Sourbeer KN, Koontz BF, Salama JK, Freedland SJ.   Are you the author?
Division of Urology, Department of Surgery, Duke University School of Medicine; Department of Biostatistics and Bioinformatics, Duke University School of Medicine; Department of Radiation Oncology Duke University School of Medicine; Division of Urology, Veterans Affairs Medical Center.  

Reference: Cancer Epidemiol Biomarkers Prev. 2014 Aug 21. pii: cebp.0236.2014.
doi: 10.1158/1055-9965.EPI-14-0236

PubMed Abstract
PMID: 25146088

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