HER2 Testing in Breast Cancer
Publication Date: June 7, 2023
Key Points
Key Points
Recommendations by the American Society of Clinical Oncology and College of American Pathologists (ASCO/CAP) human epidermal growth factor receptor 2 (HER2) Testing Expert Panel are aimed at improving the analytic validity of HER2 testing and the clinical utility of HER2 as a predictive biomarker for potential responsiveness to therapies targeting the HER2 protein.
HER2 gene amplification assessed by in situ hybridization (ISH) or protein overexpression assessed by immunohistochemistry (IHC) remains the primary predictors of responsiveness to HER2-targeted therapies in breast cancer.
Greater communication among health-care providers (especially pathologists and oncologists) and appropriate infrastructure support for specimen handling and laboratory facilities have led to observed improvements in the analytic performance and accuracy of HER2 testing.
HER2 gene amplification assessed by in situ hybridization (ISH) or protein overexpression assessed by immunohistochemistry (IHC) remains the primary predictors of responsiveness to HER2-targeted therapies in breast cancer.
Greater communication among health-care providers (especially pathologists and oncologists) and appropriate infrastructure support for specimen handling and laboratory facilities have led to observed improvements in the analytic performance and accuracy of HER2 testing.
Highlights
Highlights
...ll newly diagnosed patients with bre...
...se has a HER2/CEP17 ratio is ≥2.0 but the av...
...as an average of ≥6.0 HER2 signals/cell with...
...case has an average HER2 signals/tumor cell of...
ISH Testing
...I...
Acceptable (IHC and ISH) Tests
...(IHC and ISH) Tests...
Reporting Requirements For All Assay Types
...eporting Requirements For All Assay Types...
Optimal Tissue Handling Requirements
...e Handling Requirements...
Optimal Tissue Sectioning Requirements
...Tissue Sectioning Requirements...
Optimal Internal Validation Procedure
...al Internal Validation Procedure...