title: A comparison of hormonal profiles between breast cancer and benign breast disease: a case-control study.
abstract: BACKGROUND
  Benign breast disease (BBD), particularly proliferative BBD, is an established breast cancer risk factor. However, there has been no systematic attempt to compare the hormonal profiles of the two conditions. In a case-control investigation in Athens, Greece, we compared levels of estrogens, testosterone and insulin-like growth factor-1 (IGF-1), as well as their principal binding proteins, between breast cancer patients, women with BBD by histological type (proliferative and nonproliferative) and women with no breast pathology.
  
  
  METHODS
  We studied 466 women with incident breast cancer, 704 women with BBD and 244 healthy women. We used multiple regression to compare log-transformed serum hormone levels of breast cancer patients with those of healthy women and women with BBD by histological type (proliferative and nonproliferative BBD).
  
  
  RESULTS
  The hormonal profile of breast cancer in our study was in line with the generally accepted hormonal profile of this disease, as reported from large cohort studies. Compared with healthy women, breast cancer patients tended to have higher levels of steroid hormones. The evidence was strong for estrone (difference 21.5%, P < 0.001), weaker for testosterone (difference 15.8%, P = 0.07) and weaker still for estradiol (difference 12.0%, P = 0.18). Also compared with healthy women, breast cancer patients had barely higher levels of IGF-1 (difference 2.0%, P = 0.51), but had significantly lower levels of IGF binding protein 3 (IGFBP-3) (difference -6.7%, P = 0.001). Compared with women with BBD, breast cancer patients had nonstatistically significantly lower levels of steroid hormones, but they had higher levels of IGF-1 [difference 5.5%, 95% confidence interval (CI) 0.7% to 10.6%] and lower levels of IGFBP-3 (difference -3.7%, 95% CI -6.7% to -0.7%). Differences were more pronounced when breast cancer patients were contrasted to women with proliferative BBD.
  
  
  CONCLUSIONS
  Our findings suggest that high levels of IGF-1 may be an important factor toward the evolution of BBD to breast cancer.
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, University of Athens Medical School, Athens, Greece; Department of Epidemiology, Harvard School of Public Health, Boston, USA; Bureau of Epidemiologic Research, Academy of Athens, Athens. Electronic address: pdlagiou@med.uoa.gr.
authors.forename: P
authors.initials: P
authors.lastname: Lagiou
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, University of Athens Medical School, Athens, Greece.
authors.forename: E
authors.initials: E
authors.lastname: Samoli
authors.affiliation: Faculty of Health Professions, Athens Technological Educational Institute, Athens.
authors.forename: A
authors.initials: A
authors.lastname: Lagiou
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, University of Athens Medical School, Athens, Greece.
authors.forename: P
authors.initials: P
authors.lastname: Zourna
authors.affiliation: Bureau of Epidemiologic Research, Academy of Athens, Athens; Department of Public and Administrative Health, National School of Public Health, Athens.
authors.forename: A
authors.initials: A
authors.lastname: Barbouni
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, University of Athens Medical School, Athens, Greece.
authors.forename: C
authors.initials: C
authors.lastname: Georgila
authors.affiliation: First Department of Surgery, Elena Venizelou Hospital, Athens.
authors.forename: A
authors.initials: A
authors.lastname: Tsikkinis
authors.affiliation: 'Prolipsis' Diagnostic Center, Athens.
authors.forename: D
authors.initials: D
authors.lastname: Vassilarou
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, University of Athens Medical School, Athens, Greece.
authors.forename: P
authors.initials: P
authors.lastname: Minaki
authors.affiliation: Department of Pathology, Elena Venizelou Hospital, Athens.
authors.forename: C
authors.initials: C
authors.lastname: Sfikas
authors.affiliation: 'Biomedicine' Diagnostic Center, Athens, Greece.
authors.forename: E
authors.initials: E
authors.lastname: Spanos
authors.affiliation: Department of Epidemiology, Harvard School of Public Health, Boston, USA; Bureau of Epidemiologic Research, Academy of Athens, Athens.
authors.forename: D
authors.initials: D
authors.lastname: Trichopoulos
mesh_terms: D001941:Breast Diseases / Q000097:blood / Q000378:metabolism; D001943:Breast Neoplasms / Q000097:blood* / Q000378:metabolism; D016022:Case-Control Studies; D004967:Estrogens / Q000097:blood*; D005260:Female; D006115:Greece; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood*; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008875:Middle Aged; D012307:Risk Factors; D013739:Testosterone / Q000097:blood*
chemical_list: D004967:Estrogens; C515497:IGFBP3 protein, human; D018972:Insulin-Like Growth Factor Binding Protein 3; D013739:Testosterone; D007334:Insulin-Like Growth Factor I
keywords: IGF-1; benign breast disease; breast cancer; epidemiology; proliferative; steroid hormones