Fluorescence in situ hybridization for HER-2/neu amplification of breast carcinoma in archival fine needle aspiration biopsy specimens.
OBJECTIVE
To assess the usefulness of fluorescence in situ hybridization (FISH) for HER-2/neu amplification of breast carcinoma in archival fine needle aspiration biopsy (FNAB) specimens.


METHODS
All FISH performed on formalin-fixed, paraffin-embedded surgical specimens during January 2003-August 2003 at the University of California Irvine Medical Center were selected. Prior FNABs were retrieved. One cytologic slide was destained in each case. The results were compared with those obtained on histologic specimens using the paired t test.


RESULTS
FISH was performed on 41 surgical specimens of breast carcinoma. Thirteen patients had prior FNABs that were positive for adenocarcinoma. After hybridization on destained fine needle aspiration slides, no cells were found in 2 cases, and the results were not readable in 2 cases. In the remaining 9 cases, the results, expressed as the ratio of copies of the HER-2/neu gene to copies of the chromosome 17 centromere, were 5.10, 1.14, 1.21, 1.12, 0.74, 1.11, 1.21, 9.87 and 2.4. Results on the corresponding histologic specimens were 5.25, 1.05, 1.13, 1.22, 1.13, 1.12, 1.21, 9.35 and 2.61, respectively. No significant difference was found (p = 0.23).


CONCLUSIONS
HER-2/neu amplification status by FISH can be accurately and reliably evaluated in existing archival cytologic slides.
Gu
Mai
M
Department of Pathology, University of California Irvine Medical Center, Orange, California 92868, USA. mgu@uci.edu
Ghafari
Sophie
S
Zhao
Manxu
M
D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001109:Archives; D044963:Biopsy, Fine-Needle; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D002277:Carcinoma / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics; D005260:Female; D005784:Gene Amplification / Q000235:genetics*; D018628:Gene Dosage / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D018734:Genes, erbB-2 / Q000235:genetics*; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods / Q000639:trends; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D011237:Predictive Value of Tests; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D000068878:Trastuzumab
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab