title: Estrogen receptors in 699 primary breast cancers: a comparison of immunohistochemical and biochemical methods.
abstract: BACKGROUND
  Over the last few years, estrogen receptor (ER) determination by immunohistochemistry (ER-ICA) has been extensively used, but it still remains to be established whether this method can replace the standard biochemical technique using dextran-coated charcoal (ERDCC).
  
  
  METHODS
  ER were determined by both the dextran-coated charcoal (DCC) method and immunohistochemistry (ICA) in 699 patients with primary breast cancer; other parameters (age, pathological T-pT- and nodal status -pN-, progesterone receptors by DCC, proliferative index by ICA) were also recorded. The 'best' cut-off for ERICA was evaluated by means of Receiver Operating Characteristics (R.O.C.) analysis; logistic regression analysis was used to find adequate 'weights' for stain intensity.
  
  
  CONCLUSIONS
  A significant correlation was found between the two methods (p < 0.001). R.O.C. analysis revealed that the 'best' cut-off for the ERICA score was 45% (sensitivity 0.810, specificity 0.804). Logistic regression analysis showed that an ERICA score which also considers staining intensity does not add any useful information concerning ER content in breast cancers.
authors.affiliation: Department of Medical Oncology, University of Verona, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Molino
authors.forename: R
authors.initials: R
authors.lastname: Micciolo
authors.forename: M
authors.initials: M
authors.lastname: Turazza
authors.forename: F
authors.initials: F
authors.lastname: Bonetti
authors.forename: Q
authors.initials: Q
authors.lastname: Piubello
authors.forename: A
authors.initials: A
authors.lastname: Corgnati
authors.forename: L
authors.initials: L
authors.lastname: Sperotto
authors.forename: G
authors.initials: G
authors.lastname: Martignoni
authors.forename: A
authors.initials: A
authors.lastname: Bonetti
authors.forename: R
authors.initials: R
authors.lastname: Nortilli
mesh_terms: D001943:Breast Neoplasms / Q000648:ultrastructure*; D002606:Charcoal; D003911:Dextrans; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D012372:ROC Curve; D011960:Receptors, Estrogen / Q000032:analysis*; D013194:Staining and Labeling / Q000379:methods
chemical_list: D003911:Dextrans; D011960:Receptors, Estrogen; D002606:Charcoal