title: Detection of HER2/neu gene amplification in archival paraffin-embedded breast cancer tissues by fluorescence in situ hybridization.
abstract: We evaluated HER2/neu gene amplification by fluorescence in situ hybridization (FISH) in archival paraffin-embedded breast cancer tissues. Tumors from 63 human invasive breast cancers were categorized into two groups depending on whether the paraffin-embedded tissue blocks had been stored for more or less than 12 months duration. These were subjected to routine and modified FISH protocols. As microwave oven formalin fixation of tissues was carried out in the majority of the older archived specimens, the effect of this fixation method was also analyzed. FISH signals were obtained in all 13 archival specimens stored for less than 12 months. However, in 50 specimens stored for more than 12 months duration, the procedure was successful in only 10 specimens (20%), for which the pretreatment procedure had to be individually optimized for each specimen. There was no significant difference in the detection of FISH signals between microwave oven and routinely fixed specimens.
authors.affiliation: Department of Anatomy, National University of Singapore, Singapore.
authors.forename: Sathiyamoorthy
authors.initials: S
authors.lastname: Selvarajan
authors.forename: Boon-Huat
authors.initials: BH
authors.lastname: Bay
authors.forename: Shalawati Binte
authors.initials: SB
authors.lastname: Mamat
authors.forename: Andrew
authors.initials: A
authors.lastname: Choo
authors.forename: Khoon-Leong
authors.initials: KL
authors.lastname: Chuah
authors.forename: Christina Rudduck
authors.initials: CR
authors.lastname: Sivaswaren
authors.forename: Sim-Leng
authors.initials: SL
authors.lastname: Tien
authors.forename: Chow-Yin
authors.initials: CY
authors.lastname: Wong
authors.forename: Puay-Hoon
authors.initials: PH
authors.lastname: Tan
mesh_terms: D001943:Breast Neoplasms / Q000235:genetics*; D005260:Female; D018734:Genes, erbB-2 / Q000235:genetics*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D016612:Paraffin Embedding