@article { , title = {Human epidermal growth factor receptor 2 testing in breast cancer: American Society of Clinical Oncology/College of American Pathologists clinical practice guideline focused update}, abstract = {Purpose: To update key recommendations of the American Society of Clinical Oncology / College of American Pathologists human epidermal growth factor receptor 2 (HER2) testing in breast cancer gudeline. Methods: Based on the signals approach, an Expert Panel reviewed published literature and research survey results on the observed frequency of less common in situ hybridization (ISH) patterns to update the recommendations. Recommendations: Two recommendations addressed via correspondence in 2015 are included. First, immunohistochemistry (IHC) 2+ is defined as invasive breast cancer with weak to moderate complete membranestaining observed in.10\% of tumor cells. Second, if the initial HER2 test result in a core needle biopsy specimen of a primary breast cancer is negative, a new HER2 test may (not “must”) be ordered on the excision specimen based on specific clinical criteria. The HER2 testing algorithm for breast cancer is updated to address the recommended work-up for less common clinical scenarios (approximately 5\% of cases) observed when using a dual-probe ISH assay. These scenarios are described as ISH group 2 (HER2/chromosome enumeration probe 17 [CEP17] ratio > or = 2.0; average HER2 copy number less than 4.0 signals per cell), ISH group 3 (HER2/CEP17 ratio less than 2.0; average HER2copy number > or = 6.0 signals per cell), and ISH group 4 (HER2/CEP17 ratio less than 2.0; average HER2 copy number > or = 4.0 and less than 6.0 signals per cell). The diagnostic approach includes more rigorous interpretation criteria for ISH and requires concomitant IHC review for dual-probe ISH groups 2 to 4 to arrive at the most accurate HER2 status designation (positive or negative) based on combined interpretation of the ISH and IHC assays. The Expert Panel recommends that laboratories using single-probe ISH assays include concomitant IHC review as part of the interpretation of all single-probe ISH assay results.}, doi = {10.1200/jco.2018.77.8738}, eissn = {1527-7755}, issn = {0732-183X}, issue = {20}, journal = {Journal of Clinical Oncology}, note = {6 mo. embargo. OL 07.12.2018}, pages = {2105-2122}, publicationstatus = {Published}, publisher = {American Society of Clinical Oncology}, url = {https://nottingham-repository.worktribe.com/output/1380167}, volume = {36}, keyword = {Cancer Research, Oncology}, year = {2018}, author = {Wolff, Antonio C. and Hammond, M. Elizabeth Hale and Allison, Kimberly H. and Harvey, Brittany E. and Mangu, Pamela B. and Bartlett, John M.S. and Bilous, Michael and Ellis, Ian O. and Fitzgibbons, Patrick and Hanna, Wedad and Jenkins, Robert B. and Press, Michael F. and Spears, Patricia A. and Vance, Gail H. and Viale, Giuseppe and McShane, Lisa M. and Dowsett, Mitchell} }