Daniela Furrer1,2,3, Simon Jacob4,5,6, Chantal Caron4,5, François Sanschagrin2,4, Louise Provencher1,2,4,7, Caroline Diorio8,2,3,4. 1. Cancer Research Center at Laval University, Faculty of Medicine, Laval University, Quebec City, Canada. 2. Oncology Axis, CHU of Quebec Research Center, Laval University, Quebec City, Canada. 3. Department of Social and Preventive Medicine, Faculty of Medicine, Laval University, Quebec City, Canada. 4. Deschênes-Fabia Center for Breast Diseases, Saint-Sacrement Hospital, Quebec City, Canada. 5. Pathology Service, Saint-Sacrement Hospital, Quebec City, Canada. 6. Department of Molecular Biology, Medical Biochemistry and Pathology, Faculty of Medicine, Laval University, Quebec City, Canada. 7. Department of Surgery, Faculty of Medicine, Laval University, Quebec City, Canada. 8. Cancer Research Center at Laval University, Faculty of Medicine, Laval University, Quebec City, Canada caroline.diorio@crchudequebec.ulaval.ca.
Abstract
AIM: Immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) are common methods for assessment of human epidermal growth factor receptor 2 (HER2) in breast cancer. MATERIALS AND METHODS: In a cohort of 498 consecutive patients with breast cancer, we examined concordance between IHC and FISH for HER2 on tissue microarray (TMA) sections. In a subset of 116 specimens, we examined HER2 concordance from the block used for diagnostics and a randomly-chosen additional block (a proxy of the core biopsy). RESULTS: Overall concordance between both methods on TMA sections was 93.8% and between HER2, determined on diagnostic and additional blocks, was 93.6% for IHC and 98.0% for FISH. CONCLUSION: Since some cases were discordant, we suggest that both methods be used for HER2 assessment. The lower concordance rate between diagnostic and additional blocks using IHC compared to FISH suggests a greater variability of IHC staining across tumor regions than for FISH results. Copyright
AIM: Immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) are common methods for assessment of human epidermal growth factor receptor 2 (HER2) in breast cancer. MATERIALS AND METHODS: In a cohort of 498 consecutive patients with breast cancer, we examined concordance between IHC and FISH for HER2 on tissue microarray (TMA) sections. In a subset of 116 specimens, we examined HER2 concordance from the block used for diagnostics and a randomly-chosen additional block (a proxy of the core biopsy). RESULTS: Overall concordance between both methods on TMA sections was 93.8% and between HER2, determined on diagnostic and additional blocks, was 93.6% for IHC and 98.0% for FISH. CONCLUSION: Since some cases were discordant, we suggest that both methods be used for HER2 assessment. The lower concordance rate between diagnostic and additional blocks using IHC compared to FISH suggests a greater variability of IHC staining across tumor regions than for FISH results. Copyright
Authors: Thomas Albrecht; Melina Rausch; Stephanie Rössler; Michael Albrecht; Jana Dorothea Braun; Veronika Geissler; Arianeb Mehrabi; Monika Nadja Vogel; Anita Pathil-Warth; Gunhild Mechtersheimer; Marcus Renner; Christian Rupp; Karl Heinz Weiss; Elena Busch; Bruno Köhler; Christoph Springfeld; Peter Schirmacher; Benjamin Goeppert Journal: BMC Cancer Date: 2019-12-05 Impact factor: 4.430