title: Serum insulin-like growth factor (IGF)-I and IGF-binding protein-3 concentrations and prostate cancer risk: results from the European Prospective Investigation into Cancer and Nutrition.
abstract: BACKGROUND
  Some studies suggest that elevated serum insulin-like growth factor (IGF)-I concentrations are associated with an increased risk of prostate cancer and, in particular, with an increased risk of advanced-stage prostate cancer.
  
  
  METHODS
  We analyzed the association between prediagnostic serum concentrations of IGF-I and IGF-binding protein-3 (IGFBP-3) and prostate cancer risk in a case-control study nested in the European Prospective Investigation into Cancer and Nutrition. This study includes 630 incident prostate cancer cases and 630 matched control subjects. Odds ratios and their 95% confidence intervals (95% CI) were calculated for prostate cancer risk associated with increasing IGF-I and IGFBP-3 concentrations using conditional logistic regression.
  
  
  RESULTS
  The risk of total prostate cancer in the highest versus the lowest third of serum peptide concentration was 1.35 (95% CI, 0.99-1.82; Ptrend = 0.08) for IGF-I, 1.39 (95% CI, 1.02-1.89; Ptrend = 0.12) for the IGF-I residuals after adjusting for IGFBP-3, 1.22 (95% CI, 0.92-1.64; Ptrend = 0.38) for IGFBP-3, and 1.01 (95% CI, 0.74-1.37; Ptrend = 0.75) for the IGFBP-3 residuals after adjusting for IGF-I. There was no significant difference in the association of peptide hormones and prostate cancer by stage of disease, although the association of serum IGF-I concentration with risk was slightly stronger for advanced-stage disease; the odds ratio for the highest versus the lowest third was 1.65 (95% CI, 0.88-3.08; Ptrend = 0.21) for IGF-I and 1.76 (95% CI, 0.92-3.40; Ptrend = 0.11) for IGF-I adjusted for IGFBP-3.
  
  
  CONCLUSIONS
  In this large nested case-control study, serum IGF-I concentration is not strongly associated with prostate cancer risk, although the results are compatible with a small increase in risk, particularly for advanced-stage disease; no association for IGFBP-3 was observed.
authors.affiliation: Cancer Research UK Epidemiology Unit, University of Oxford, Oxford OX3 7LF, United Kingdom. naomi.allen@ceu.ox.ac.uk
authors.forename: Naomi E
authors.initials: NE
authors.lastname: Allen
authors.forename: Timothy J
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authors.forename: Ruth C
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authors.forename: Andrew W
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authors.lastname: Roddam
authors.forename: Sabina
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authors.lastname: Rinaldi
authors.forename: Lars
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authors.forename: Sabine
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authors.lastname: Rohrmann
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authors.forename: Nina Føns
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authors.forename: Anne
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authors.lastname: Tjønneland
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authors.initials: H
authors.lastname: Grønbaek
authors.forename: Kim
authors.initials: K
authors.lastname: Overvad
authors.forename: Lambartus
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authors.lastname: Kiemeney
authors.forename: H Bas
authors.initials: HB
authors.lastname: Bueno-de-Mesquita
authors.forename: Sheila
authors.initials: S
authors.lastname: Bingham
authors.forename: Kay Tee
authors.initials: KT
authors.lastname: Khaw
authors.forename: Rosario
authors.initials: R
authors.lastname: Tumino
authors.forename: Franco
authors.initials: F
authors.lastname: Berrino
authors.forename: Amalia
authors.initials: A
authors.lastname: Mattiello
authors.forename: Carlotta
authors.initials: C
authors.lastname: Sacerdote
authors.forename: Domenico
authors.initials: D
authors.lastname: Palli
authors.forename: José Ramón
authors.initials: JR
authors.lastname: Quirós
authors.forename: Eva
authors.initials: E
authors.lastname: Ardanaz
authors.forename: Carmen
authors.initials: C
authors.lastname: Navarro
authors.forename: Nerea
authors.initials: N
authors.lastname: Larrañaga
authors.forename: Carlos
authors.initials: C
authors.lastname: Gonzalez
authors.forename: Maria-José
authors.initials: MJ
authors.lastname: Sanchez
authors.forename: Antonia
authors.initials: A
authors.lastname: Trichopoulou
authors.forename: Cryssoula
authors.initials: C
authors.lastname: Travezea
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Trichopoulos
authors.forename: Mazda
authors.initials: M
authors.lastname: Jenab
authors.forename: Pietro
authors.initials: P
authors.lastname: Ferrari
authors.forename: Elio
authors.initials: E
authors.lastname: Riboli
authors.forename: Rudolf
authors.initials: R
authors.lastname: Kaaks
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood*; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011471:Prostatic Neoplasms / Q000097:blood* / Q000473:pathology*; D012307:Risk Factors
chemical_list: D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I