title: Testing for HER-2/neu in breast cancer: is fluorescence in situ hybridization superior in predicting outcome?
abstract: Testing for alterations in HER-2/neu in breast cancer has become increasingly popular in recent years, particularly with the recent development of a humanized antiHER-2/neu monoclonal antibody, trastuzumab, which is currently being employed in conjunction with cytotoxic chemotherapy to treat metastatic breast cancer in patients whose tumors exhibit this HER-2/neu alteration. Controversy exists not only on the optimal method of laboratory testing for this HER-2/neu alteration (i.e., fluorescence in situ hybridization (FISH) versus immunohistochemistry (IHC) versus others), but also on the type of reagents used for a given method. A plethora of published studies on tissue-based HER-2/neu testing has recently appeared in many peer-reviewed journals; many have concluded that IHC could be used as a first-line screening test, with the recommendation of FISH to confirm indeterminate results. In contrast to these studies, a recent study by Pauletti et al. showed that HER-2/neu testing by IHC does not predict clinical outcome as accurately as does FISH. This commentary discusses the findings of this study, within a broader review of critical issues relating to HER-2/neu testing in breast cancer.
authors.affiliation: PhenoPath Laboratories, 551 North 34th Street, Suite 100, Seattle, WA 98103, USA.
authors.forename: Hadi
authors.initials: H
authors.lastname: Yaziji
authors.forename: Allen M
authors.initials: AM
authors.lastname: Gown
mesh_terms: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000235:genetics / Q000401:mortality; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D017404:In Situ Hybridization, Fluorescence; D008403:Mass Screening; D010865:Pilot Projects; D011379:Prognosis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis / Q000235:genetics; D015203:Reproducibility of Results; D015996:Survival Rate; D000068878:Trastuzumab
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D018719:Erb-b2 Receptor Tyrosine Kinases; D000068878:Trastuzumab