title: HER-2/neu gene amplification characterized by fluorescence in situ hybridization: poor prognosis in node-negative breast carcinomas.
abstract: OBJECTIVE
  The HER-2/neu gene codes for a membrane receptor protein that is homologous, but distinct from the epidermal growth factor receptor. This investigation was performed to validate fluorescence in situ hybridization (FISH) as a sensitive and specific method for assessing HER-2/neu gene amplification in archival tissue and to test whether this alteration is associated with poor prognosis.
  
  
  METHODS
  HER-2/neu gene amplification was determined by FISH in 140 archival breast cancers, previously characterized for gene amplification by Southern hybridization or dot-blot hybridization, and for gene expression by Northern hybridization, Western immunoblot, or immunohistochemistry. A separate cohort of 324 node-negative breast cancers was assessed for amplification by FISH to determine the utility of HER-2/neu gene amplification.
  
  
  RESULTS
  Relative to solid-matrix blotting procedures, FISH analysis of HER-2/neu gene amplification showed a sensitivity of 98% and a specificity of 100% in 140 breast cancers. Among patients treated by surgery only, the relative risks (relative hazard) of early recurrence (recurrent disease within 24 months of diagnosis), recurrent disease (at any time), and disease-related death were statistically significantly associated with amplification. The prognostic information contributed by HER-2/neu amplification was independent of the other markers studied.
  
  
  CONCLUSIONS
  FISH was an alternative technique for determining gene amplification and had some distinct advantages over Southern hybridization. Our results demonstrate that HER-2/neu gene amplification in the absence of adjuvant therapy is an independent predictor of poor clinical outcome and is a stronger discriminant than tumor size. Women with small tumors that had gene amplification were at increased risk of recurrence and disease-related death.
authors.affiliation: Norris Comprehensive Cancer Center and Department of Pathology, University of Southern California School of Medicine, Los Angeles, CA 90033, USA. villalob@hsc.usc.edu
authors.forename: M F
authors.initials: MF
authors.lastname: Press
authors.forename: L
authors.initials: L
authors.lastname: Bernstein
authors.forename: P A
authors.initials: PA
authors.lastname: Thomas
authors.forename: L F
authors.initials: LF
authors.lastname: Meisner
authors.forename: J Y
authors.initials: JY
authors.lastname: Zhou
authors.forename: Y
authors.initials: Y
authors.lastname: Ma
authors.forename: G
authors.initials: G
authors.lastname: Hung
authors.forename: R A
authors.initials: RA
authors.lastname: Robinson
authors.forename: C
authors.initials: C
authors.lastname: Harris
authors.forename: A
authors.initials: A
authors.lastname: El-Naggar
authors.forename: D J
authors.initials: DJ
authors.lastname: Slamon
authors.forename: R N
authors.initials: RN
authors.lastname: Phillips
authors.forename: J S
authors.initials: JS
authors.lastname: Ross
authors.forename: S R
authors.initials: SR
authors.lastname: Wolman
authors.forename: K J
authors.initials: KJ
authors.lastname: Flom
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000235:genetics; D001943:Breast Neoplasms / Q000235:genetics / Q000401:mortality / Q000473:pathology*; D005260:Female; D005784:Gene Amplification; D006801:Humans; D015151:Immunoblotting; D017404:In Situ Hybridization, Fluorescence; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics*; D012680:Sensitivity and Specificity; D015996:Survival Rate
chemical_list: D014408:Biomarkers, Tumor; D018719:Erb-b2 Receptor Tyrosine Kinases