Detection of HER2/neu gene amplification in archival paraffin-embedded breast cancer tissues by fluorescence in situ hybridization.
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.
Selvarajan
Sathiyamoorthy
S
Department of Anatomy, National University of Singapore, Singapore.
Bay
Boon-Huat
BH
Mamat
Shalawati Binte
SB
Choo
Andrew
A
Chuah
Khoon-Leong
KL
Sivaswaren
Christina Rudduck
CR
Tien
Sim-Leng
SL
Wong
Chow-Yin
CY
Tan
Puay-Hoon
PH
D001943:Breast Neoplasms / Q000235:genetics*; D005260:Female; D018734:Genes, erbB-2 / Q000235:genetics*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D016612:Paraffin Embedding