title: Prostate volume modifies the association between obesity and prostate cancer or high-grade prostatic intraepithelial neoplasia.
abstract: The relationship between obesity and prostate cancer remains unclear. We investigated the effect of prostate volume on the obesity and prostate cancer association. With a multi-centered, rapid-recruitment protocol, weight and body size measurements were collected prior to diagnosis, and medical charts were reviewed for pathology results (n = 420 controls, 119 high-grade prostatic intraepithelial neoplasia (PIN) cases, and 286 cancer cases (41% Gleason > 6). In multivariable logistic regression models adjusting for age, PSA levels and history, DRE results, and number of cores at biopsy, the association between BMI and cancer was restricted to men with a smaller prostate volume (volume < 40 cm(3): OR(BMI > or = 30) = 2.17 (1.09, 4.32), p (trend) = 0.02; volume > or = 40 cm(3): OR(BMI > or = 30) = 0.77 (0.34, 1.77), p (trend) = 0.17; p (interaction) = 0.03). Similarly, the WHR and PIN association was significantly modified by prostate volume (volume < 40 cm(3): OR((WHR: Tertile 3 vs. T1)) = 3.76 (1.54, 9.21) (p (trend) < 0.01); volume > or = 40 m(3): OR((WHR: T3 vs. T1)) = 0.63 (0.32, 1.23) (p (trend) = 0.17); p (interaction) < 0.01). In conclusion, prostate volume acts as a modifier, and BMI and WHR are significantly associated with prostate cancer or PIN, respectively, in the absence of biopsy sampling error derived from obesity-related prostate enlargement.
authors.affiliation: Vanderbilt Epidemiology Center, Vanderbilt University Medical Center, 1215 21St Ave. South, Nashville, TN 37232-8300, USA. jay.fowke@vanderbilt.edu
authors.forename: Jay H
authors.initials: JH
authors.lastname: Fowke
authors.forename: Saundra S
authors.initials: SS
authors.lastname: Motley
authors.forename: Marcia
authors.initials: M
authors.lastname: Wills
authors.forename: Michael S
authors.initials: MS
authors.lastname: Cookson
authors.forename: Raoul S
authors.initials: RS
authors.lastname: Concepcion
authors.forename: Charles W
authors.initials: CW
authors.lastname: Eckstein
authors.forename: Sam S
authors.initials: SS
authors.lastname: Chang
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Smith
mesh_terms: D000368:Aged; D015992:Body Mass Index; D016022:Case-Control Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications* / Q000503:physiopathology; D011467:Prostate / Q000033:anatomy & histology / Q000502:physiology*; D019048:Prostatic Intraepithelial Neoplasia / Q000453:epidemiology* / Q000473:pathology; D011471:Prostatic Neoplasms / Q000453:epidemiology* / Q000473:pathology; D018570:Risk Assessment; D012307:Risk Factors; D013714:Tennessee / Q000453:epidemiology