title: Augmented serum levels of the IGF-I/IGF-binding protein-3 ratio in pre-menopausal patients with type I breast cysts.
abstract: OBJECTIVE
  Gross cystic disease (GCD) is the most common benign breast pathology. Although breast cysts are not considered pre-malignant lesions, an increased risk of breast cancer has been reported for patients with type I cysts (Na(+)/K(+)<3). Furthermore, an augmented IGF-I/IGF-binding protein-3 (IGFBP-3) ratio has been described in breast cancer patients. The objective was to evaluate serum IGF-I and binding protein concentrations of type I and type II cyst patients as compared with healthy women.
  
  
  METHODS
  Twenty-four patients with type I cysts, 17 with type II cysts and 25 healthy women were evaluated. Serum IGF-I, IGFBP-3 and IGFBP-1 concentrations were measured by IRMA.
  
  
  RESULTS
  IGF-I concentrations were significantly higher in sera from patients with type I cysts than in patients with type II cysts. A highly significant decrease of IGFBP-3, the major IGFBP, was found in patients with type I cysts with respect to healthy women, whereas no significant difference was evident between the different cyst types. The IGF-I/IGFBP-3 ratio, an estimate of biologically active IGF-I, was very significantly higher in patients with type I cysts than in both type II patients and healthy women. IGFBP-1 levels were significantly lower in patients with type I than in controls and type II cysts. The IGF-I/IGFBP-1 ratio was significantly higher in patients with type I cysts than in type II bearers and healthy women. Estrogen levels correlated with IGF-I in patients and controls.
  
  
  CONCLUSIONS
  The enhanced levels of IGF-I/IGFBP-3 found in patients with type I cysts could eventually be associated with the increased risk of breast cancer described for this group.
authors.affiliation: Instituto de Biología y Medicina Experimental, Universidad Nacional de La Plata, Buenos Aires, Argentina.
authors.forename: Pablo J
authors.initials: PJ
authors.lastname: Enriori
authors.forename: Carlos R
authors.initials: CR
authors.lastname: Fischer
authors.forename: Jorge R
authors.initials: JR
authors.lastname: Gori
authors.forename: Alberto E
authors.initials: AE
authors.lastname: Etkin
authors.forename: Ricardo S
authors.initials: RS
authors.lastname: Calandra
authors.forename: Isabel A
authors.initials: IA
authors.lastname: Lüthy
mesh_terms: D000328:Adult; D001941:Breast Diseases / Q000097:blood*; D003560:Cysts / Q000097:blood*; D005260:Female; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood*; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008875:Middle Aged; D017697:Premenopause / Q000097:blood*
chemical_list: D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I