title: HER-2/neu evaluation by immunohistochemistry and fluorescence in situ hybridization in breast cancer: implications for daily laboratory practice.
abstract: BACKGROUND
  HER-2/neu status was determined by immunohistochemistry (IHC) and fluorescence in situ hybridisation (FISH) methods in more than 300 paraffin-embedded primary breast cancer samples.
  
  
  METHODS
  HER-2/neu status was determined by FISH using the PathVysion kit (Vysis) and by IHC using either a monoclonal antibody CB11 or a cocktail of antibodies: the monoclonal TAB250 and the polyclonal pAb1.
  
  
  RESULTS
  Of the 324 cases evaluable by IHC, 65 out of 318 (20%) and 24 out of 324 (7%) were scored as positive when using the antibody cocktail and the CB11, respectively. HER-2/neu gene amplification occured in 64 out of 324 cases (20%). Concordance of FISH and IHC was found in 285 out of 318 cases (90%) and 278 out of 324 cases (86%) using the cocktail and the CB11, respectively.
  
  
  CONCLUSIONS
  The cost-effectiveness analysis revealed that the use of a sensitive IHC method followed by confirmation of positive results by FISH considerably decreased the FISH costs and may become standard practice for HER-2/neu evaluation.
authors.affiliation: Pathology Department, Jules Bordet Institute, Brussels, Belgium. denis.larsinomt@bordet.be
authors.forename: Denis
authors.initials: D
authors.lastname: Larsimont
authors.forename: Angelo
authors.initials: A
authors.lastname: Di Leo
authors.forename: Ghizlane
authors.initials: G
authors.lastname: Rouas
authors.forename: Marianne
authors.initials: M
authors.lastname: Paesmans
authors.forename: Fabiano
authors.initials: F
authors.lastname: Ferreira-Filho
authors.forename: Chantal
authors.initials: C
authors.lastname: Bernard
authors.forename: Fatima
authors.initials: F
authors.lastname: Cardoso
authors.forename: Alain
authors.initials: A
authors.lastname: Verhest
authors.forename: Martine J
authors.initials: MJ
authors.lastname: Piccart
authors.forename: David
authors.initials: D
authors.lastname: Gancberg
mesh_terms: D000911:Antibodies, Monoclonal; D001943:Breast Neoplasms / Q000235:genetics / Q000473:pathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D007753:Laboratories / Q000592:standards*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis* / Q000235:genetics*; D015203:Reproducibility of Results
chemical_list: D000911:Antibodies, Monoclonal; D018719:Erb-b2 Receptor Tyrosine Kinases