Emerging technologies for assessing HER2 amplification.
Patients with human epidermal growth factor receptor-2 (HER2)+ breast cancer are eligible for trastuzumab treatment; therefore, accurate assessment of HER2 status is essential. Until recently, only 2 methods were validated for determining the HER2 status of breast tumors in the routine diagnostic setting: immunohistochemical analysis and fluorescence in situ hybridization (FISH). Recently, bright-field in situ hybridization techniques such as chromogenic in situ hybridization (CISH) and silver-enhanced in situ hybridization (SISH), which combine features of immunohistochemical analysis and FISH, have been introduced for the determination of HER2 status. These new techniques use a peroxidase enzyme-labeled probe with chromogenic detection, instead of a fluorescent-labeled probe, allowing results to be visualized by standard bright-field microscopy. Thus, the histologic features and HER2 status of a specimen can be evaluated in parallel. Moreover, signals do not decay over time. This review discusses recent publications regarding CISH and SISH testing, including results scoring and concordance between FISH and immunohistochemical analysis.
Penault-Llorca
Frédérique
F
Départment de Pathologie, Centre Jean Perrin, 63011 Clermont-Ferrand Cedex, France.
Bilous
Michael
M
Dowsett
Mitch
M
Hanna
Wedad
W
Osamura
Robert Yoshiyuki
RY
Rüschoff
Josef
J
van de Vijver
Marc
M
D000465:Algorithms; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D001943:Breast Neoplasms / Q000235:genetics; D002863:Chromogenic Compounds; D005784:Gene Amplification; D018734:Genes, erbB-2 / Q000235:genetics*; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D017403:In Situ Hybridization / Q000379:methods; D017404:In Situ Hybridization, Fluorescence / Q000379:methods; D015588:Observer Variation; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000096:biosynthesis / Q000235:genetics; D012834:Silver; D000068878:Trastuzumab
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D002863:Chromogenic Compounds; D018719:Erb-b2 Receptor Tyrosine Kinases; D012834:Silver; D000068878:Trastuzumab; C508053:ERBB2 protein, human