Monday 28 November 2011
HER2 immunochemistry; HER2 IHC, ERBB IHC; HER2 quantification
The human epidermal growth factor receptor 2 (HER2) is an established biomarker for management of patients with breast cancer.
The currently FDA-approved methods for HER2 quantification are not able to give a quantitative measure of HER2 heterogeneity of expression. It has been developed an immunofluorescence assay to quantify HER2 on FFPE samples. Coupled with automated image analysis, this assay is able to quantify HER2 expression at the single cell level, and may constitute a means to understand the predictive and/or prognostic role of the heterogeneity of HER2 expression for patient response to HER2-targeted therapies.
HER2 IHC digital image analysis
While conventional testing of HER2 protein expression is based on semi-quantitative visual scoring of the immunohistochemistry (IHC) result, efforts to reduce inter-observer variation and to produce continuous estimates of the IHC data are potentiated by digital image analysis technologies.
HER2 IHC digital image analysis based on membrane connectivity estimate was in almost perfect agreement with the visual evaluation of the pathologist and more accurate in detection of HER2 FISH-positive patients.
Most immediate benefit of integrating the DA algorithm into the routine pathology HER2 testing may be obtained by alerting/reassuring pathologists of potentially misinterpreted IHC 0/1+ versus 2+ cases.
High concordance between HercepTest immunohistochemistry and ERBB2 fluorescence in situ hybridization before and after implementation of American Society of Clinical Oncology/College of American Pathology 2007 guidelines. Vergara-Lluri ME, Moatamed NA, Hong E, Apple SK. Mod Pathol. 2012 Jun 15. PMID: 22699517
Membrane connectivity estimated by digital image analysis of HER2 immunohistochemistry is concordant with visual scoring and fluorescence in situ hybridization results: algorithm evaluation on breast cancer tissue microarrays. Laurinaviciene A, Dasevicius D, Ostapenko V, Jarmalaite S, Lazutka J, Laurinavicius A. Diagn Pathol. 2011 Sep 23;6:87. PMID: 21943197 [Free]
Confirmation of a low HER2 positivity rate of breast carcinomas - limitations of immunohistochemistry and in situ hybridization. Vogel UF. Diagn Pathol. 2010 Jul 29;5:50. PMID: 20670419 [Free]