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Polónia A, Canelas C, Caramelo A. The spectrum of HER2 expression in breast cancer: linking immunohistochemistry quantification with in situ hybridization assay. Virchows Arch 2022; 480:1171-1179. [PMID: 35137279 DOI: 10.1007/s00428-022-03290-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Revised: 01/06/2022] [Accepted: 01/29/2022] [Indexed: 12/25/2022]
Abstract
We aimed to document the pathological characteristics of breast cancer (BC) cases with different scores of HER2 by immunohistochemistry (IHC), as well as to establish a relationship between HER2 expression and HER2 amplification by in situ hybridization (ISH). A cohort of 258 primary BC cases was evaluated for HER2 gene amplification with bright-field ISH. All HER2-negative and HER2-positive cases by IHC were concordant with the ISH classification. BC cases with score of 0 had lower average of HER2 copy number compared to cases with score of 1 + . HER2-equivocal cases by IHC had intermediate pathological characteristics between HER2-negative and HER2-positive cases. About 12% of HER2-equivocal cases were classified as ISH-positive. HER2-equivocal cases with HER2 gene amplification had proliferation index, HER2/CEP17 ratio, and average of HER2 copy number between HER2-equivocal cases without HER2 gene amplification and HER2-positive cases by IHC. Additionally, HER2-equivocal cases with HER2 amplification had score of 2 + in at least 50% of the total tumor area, with a proportion of ISH-positive cases increasing with the amount of score of 2 + present in the tumor. The quantification of score of 2 + in the tumor predicted the ISH classification with an AUC of 0.902. A logistic regression model using the same HER2 quantification and the nuclear score was able to increase the abovementioned prediction to an AUC of 0.929. As such, we were able to link HER2 quantification by IHC and morphological analysis with HER2 amplification by ISH.
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Affiliation(s)
- António Polónia
- Department of Pathology, Ipatimup Diagnostics, Institute of Molecular Pathology and Immunology, University of Porto, Rua Júlio Amaral de Carvalho, 45, 4200-135, Porto, Portugal. .,I3S - Instituto de Investigação e Inovação em Saúde, University of Porto, Porto, Portugal.
| | - Carolina Canelas
- Department of Pathology, Ipatimup Diagnostics, Institute of Molecular Pathology and Immunology, University of Porto, Rua Júlio Amaral de Carvalho, 45, 4200-135, Porto, Portugal.,I3S - Instituto de Investigação e Inovação em Saúde, University of Porto, Porto, Portugal
| | - Ana Caramelo
- Department of Pathology, Ipatimup Diagnostics, Institute of Molecular Pathology and Immunology, University of Porto, Rua Júlio Amaral de Carvalho, 45, 4200-135, Porto, Portugal.,I3S - Instituto de Investigação e Inovação em Saúde, University of Porto, Porto, Portugal
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2
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Polónia A, Caramelo A. HER2 in situ hybridization test in breast cancer: quantifying margins of error and genetic heterogeneity. Mod Pathol 2021; 34:1478-1486. [PMID: 33980971 DOI: 10.1038/s41379-021-00813-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 03/27/2021] [Accepted: 03/29/2021] [Indexed: 11/09/2022]
Abstract
The aim of the present study was to evaluate the effect of counting increasing number of invasive cancer cells in the result of the HER2 in situ hybridization (ISH) test in breast cancer as well as to compare two different approaches of measuring genomic heterogeneity (single cell and population based). A cohort of 100 consecutive breast cancer cases (primary and metastatic) were evaluated for HER2 gene amplification with bright-field ISH. The evaluation of the samples included scoring 20 nuclei, in five different areas, measuring the margins of error for each case. Genomic heterogeneity (GH) was defined by the 2018 ASCO/CAP guideline as a discrete population of tumor cells with HER2 amplification. We also evaluated GH as single tumor cells with HER2 amplification. The stabilization of the coefficient of variation of HER2/CEP17 ratio requires about 60 invasive cancer cells. The average margin of error of HER2/CEP17 ratio and of HER2 copy number was 0.40 and 0.53, respectively, when counting 20 cells, decreasing to 0.20 and 0.26 when counting 100 cells. Population GH was observed in 1% of the cases, while single cell GH was observed in 27% of the cases, reaching its maximum value in cases near the thresholds of positivity. Therefore, margins of error in HER2 ISH test are high, and the minimal cell number recommended in current guidelines should be raised to at least 60 cells. Population GH is a rare event and single cell GH is maximal in cases near the thresholds.
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Affiliation(s)
- António Polónia
- Department of Pathology, Ipatimup Diagnostics, Institute of Molecular Pathology and Immunology, University of Porto, Porto, Portugal. .,I3S - Instituto de Investigação e Inovação em Saúde, University of Porto, Porto, Portugal.
| | - Ana Caramelo
- Department of Pathology, Ipatimup Diagnostics, Institute of Molecular Pathology and Immunology, University of Porto, Porto, Portugal.,I3S - Instituto de Investigação e Inovação em Saúde, University of Porto, Porto, Portugal
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3
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Kim MC, Kang SH, Choi JE, Bae YK. Impact of the Updated Guidelines on Human Epidermal Growth Factor Receptor 2 (HER2) Testing in Breast Cancer. J Breast Cancer 2020; 23:484-497. [PMID: 33154824 PMCID: PMC7604374 DOI: 10.4048/jbc.2020.23.e53] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 09/13/2020] [Indexed: 01/13/2023] Open
Abstract
Purpose In 2007, the American Society of Clinical Oncology and the College of American Pathologists had established a human epidermal growth factor receptor 2 (HER2) testing guideline, which was updated in 2013 and subsequently in 2018. We assessed the clinical impact of the recent update by comparing the in situ hybridization (ISH) results based on the 2007, 2013, and 2018 guidelines. Methods We assessed 2 cohorts. The first cohort included 1,161 primary invasive breast cancer (IBC) samples including 18 bilateral IBC cases, with both immunohistochemistry (IHC) and silver-enhanced ISH (SISH) results available for the HER2 status. The second cohort included 160 IBC cases with equivocal HER2 IHC, assessed using SISH. We retrospectively evaluated and compared the HER2 SISH results. Results There were 22 (1.9%) and 20 (12.5%) cases with altered SISH results according to the 2013 guidelines in cohorts 1 and 2, respectively. As per the 2018 guidelines, final HER2 statuses of 16 (1.4%) and 14 (8.5%) cases changed in cohorts 1 and 2, respectively. The 2013 guidelines increased the positive rate compared to the 2007 guidelines, in both cohorts (0.6% and 6.2%, respectively). Most equivocal cases in cohorts 1 (92.3%) and 2 (100%) as per the 2013 guidelines were reclassified as HER2-negative according to the 2018 guidelines. The 2018 guidelines increased the negative rates (1.3% in cohort 1 and 8.7% in cohort 2) and slightly decreased the positive rates (−0.2% in cohort 1 and −3.1% in cohort 2), compared to the 2013 guidelines. With each update, minor changes in the positive and negative rates were observed in whole breast cancer samples (cohort 1). However, the 2018 guidelines affected previously defined HER2-positive IBC with equivocal IHC results. Conclusion Under the 2013 guidelines, the positive and equivocal cases increased. However, the 2018 guidelines eliminated ambiguous cases by reclassifying them as HER2-negative.
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Affiliation(s)
- Min Chong Kim
- Department of Pathology, Yeungnam University College of Medicine, Daegu, Korea
| | - Su Hwan Kang
- Department of Breast Surgery, Yeungnam University College of Medicine, Daegu, Korea
| | - Jung Eun Choi
- Department of Breast Surgery, Yeungnam University College of Medicine, Daegu, Korea
| | - Young Kyung Bae
- Department of Pathology, Yeungnam University College of Medicine, Daegu, Korea
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Pasricha S, Menon V, Gupta G, Kamboj M, Sharma A, Durga G, Tripathi R, Batra U, Jajodia A, Koyyala VPB, Agrawal C, Doval DC, Mehta A. Impact of 2018 ASCO/CAP guidelines on HER-2 reporting categories of IHC and reflex FISH in breast cancer. Breast J 2020; 26:2213-2216. [PMID: 32864808 DOI: 10.1111/tbj.14031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 08/05/2020] [Accepted: 08/05/2020] [Indexed: 01/13/2023]
Abstract
Human epidermal growth factor receptor 2 (HER-2) is an established prognostic and predictive biomarker for breast cancer. To ensure accuracy and uniformity for HER-2 testing, ASCO/CAP published guidelines in 2007 which were updated in 2013 and recently in 2018. In this first study from Indian Oncology center, we evaluated the impact of 2018 ASCO/CAP guidelines. We found a substantial decrease in equivocal IHC cases (P-value < .00001). On reclassification, a total of 5.6% cases from equivocal and positive categories (2013 guidelines) shifted to the negative FISH result category (P-value < .0001), with adoption of 2018 guidelines and eliminated the double equivocal cases.
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Affiliation(s)
- Sunil Pasricha
- Department of Pathology, Rajiv Gandhi Cancer Institute and Research Centre, Delhi, India
| | - Vidya Menon
- Department of Pathology, Rajiv Gandhi Cancer Institute and Research Centre, Delhi, India
| | - Gurudutt Gupta
- Department of Pathology, Rajiv Gandhi Cancer Institute and Research Centre, Delhi, India
| | - Meenakshi Kamboj
- Department of Pathology, Rajiv Gandhi Cancer Institute and Research Centre, Delhi, India
| | - Anila Sharma
- Department of Pathology, Rajiv Gandhi Cancer Institute and Research Centre, Delhi, India
| | - Garima Durga
- Department of Pathology, Rajiv Gandhi Cancer Institute and Research Centre, Delhi, India
| | - Rupal Tripathi
- Department of Research, Rajiv Gandhi Cancer Institute and Research Centre, Delhi, India
| | - Ullas Batra
- Department of Medical Oncology, Rajiv Gandhi Cancer Institute and Research Centre, Delhi, India
| | - Ankush Jajodia
- Department of Radiodiagnosis, Rajiv Gandhi Cancer Institute and Research Centre, Delhi, India
| | | | - Chaturbhuj Agrawal
- Department of Medical Oncology, Rajiv Gandhi Cancer Institute and Research Centre, Delhi, India
| | - Dinesh C Doval
- Department of Medical Oncology, Rajiv Gandhi Cancer Institute and Research Centre, Delhi, India
| | - Anurag Mehta
- Department of Pathology, Rajiv Gandhi Cancer Institute and Research Centre, Delhi, India
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Ferreira D, Soares M, Correia J, Adega F, Ferreira F, Chaves R. Assessment of ERBB2 and TOP2α gene status and expression profile in feline mammary tumors: findings and guidelines. Aging (Albany NY) 2020; 11:4688-4705. [PMID: 31301170 PMCID: PMC6660035 DOI: 10.18632/aging.102079] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 07/02/2019] [Indexed: 12/18/2022]
Abstract
In humans, the ERBB2 gene amplification and overexpression are biomarkers for invasive breast cancer and a therapeutic target. Also, TOP2α gene aberrations predict the response to anthracycline-based adjuvant chemotherapy. Although feline mammary tumors (FMTs) are good models in comparative oncology, scarce data is available regarding the ERBB2 and TOP2α status. In this study, and for the first time, the ERBB2 DNA status and RNA levels of intracellular (ICD) and extracellular (ECD) coding regions were compared with TOP2α gene status and expression profile, in samples of FMTs and disease-free tissues from the same animal. Results showed that ERBB2 and TOP2α gene status are highly correlated (r=0.87, p<0.0001, n=25), with few tumor samples presenting amplification. Also, the majority of the FMTs showed ERBB2 overexpression coupled with TOP2α overexpression (r=0.87, p<0.0001, n=27), being the ERBB2-ICD and ECD transcripts highly correlated (r=0.97, p<0.0001, n=27). Significant associations were found between TOP2α gene status or ERBB2 and TOP2α RNA levels with several clinicopathological parameters. This work highlights the need of experimental designs for a precise evaluation of ERBB2 and TOP2α gene status and its expression in FMTs, to improve their clinical management and to further validate them as a suitable model for comparative oncology studies.
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Affiliation(s)
- Daniela Ferreira
- CAG - Laboratory of Cytogenomics and Animal Genomics, Department of Genetics and Biotechnology, University of Trás-os-Montes e Alto Douro, 5000-801 Vila Real, Portugal.,BioISI - Biosystems and Integrative Sciences Institute, Faculty of Sciences, University of Lisbon, Lisbon 1749-016, Portugal
| | - Maria Soares
- Research Center for Biosciences and Health Technologies (CBiOS), Faculdade de Medicina Veterinária, Universidade Lusófona de Humanidades e Tecnologias (ULHT), Lisbon 1749-024, Portugal
| | - Jorge Correia
- CIISA - Centro de Investigação Interdisciplinar em Sanidade Animal, Faculdade de Medicina Veterinária, Universidade de Lisboa, Avenida da Universidade Técnica, Lisbon 1300-477, Portugal
| | - Filomena Adega
- CAG - Laboratory of Cytogenomics and Animal Genomics, Department of Genetics and Biotechnology, University of Trás-os-Montes e Alto Douro, 5000-801 Vila Real, Portugal.,BioISI - Biosystems and Integrative Sciences Institute, Faculty of Sciences, University of Lisbon, Lisbon 1749-016, Portugal
| | - Fernando Ferreira
- CIISA - Centro de Investigação Interdisciplinar em Sanidade Animal, Faculdade de Medicina Veterinária, Universidade de Lisboa, Avenida da Universidade Técnica, Lisbon 1300-477, Portugal
| | - Raquel Chaves
- CAG - Laboratory of Cytogenomics and Animal Genomics, Department of Genetics and Biotechnology, University of Trás-os-Montes e Alto Douro, 5000-801 Vila Real, Portugal.,BioISI - Biosystems and Integrative Sciences Institute, Faculty of Sciences, University of Lisbon, Lisbon 1749-016, Portugal
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Machado-Neves R, Vale J, Eloy C, Polónia A. HER2 genomic heterogeneity is a frequent event in gastroesophageal adenocarcinoma and correlates with tumor morphology. Pathol Res Pract 2020; 216:153090. [PMID: 32825958 DOI: 10.1016/j.prp.2020.153090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/25/2020] [Accepted: 06/26/2020] [Indexed: 01/08/2023]
Abstract
AIM To characterize a cohort of gastro-esophageal adenocarcinomas (GEA) evaluated for HER2 gene amplification using bright field in situ hybridization (ISH) following the 2016 guidelines for GEA and correlating the results with clinico-pathological features. It was also aimed to evaluate the effect of applying the ISH criteria from the 2018 guidelines for breast cancer (BC) in the same GEA cases. MATERIALS AND METHODS 159 GEA cases collected in a period of 59 months were evaluated for HER2 gene amplification by ISH according to GEA and BC guidelines. All cases were reviewed for histological type, grading and presence of signet ring cells. RESULTS Most of the cases refereed to ISH were HER2 equivocal (57.9 %) by immunohistochemistry. According to the GEA guideline, 131 cases were HER2-negative (87.3 %) and 19 cases were HER2-positive (12.7 %). According to the BC guideline, 133 cases were HER2-negative (88.7 %) and 17 cases were HER2-positive (11.3 %), being statistically similar to the results obtained with the GEA guideline. HER2 genomic heterogeneity was detected in 31.6 % of the HER2-positive cases, almost exclusively in tubular adenocarcinoma. We observed a significant association between HER2 gene amplification and tubular adenocarcinomas, and absence of signet ring cells. The only case with HER2 gene amplification and presence of signet ring cells was a mixed carcinoma, where the signet ring cells represented the non-amplified component. CONCLUSIONS HER2 positivity rate was similar when applying the GEA or the BC guidelines. We also establish a tight association between morphology and HER2 gene amplification.
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Affiliation(s)
- Raquel Machado-Neves
- Department of Pathology, Hospital Pedro Hispano, ULS Matosinhos, Rua Dr. Eduardo Torres, 4464-513, Senhora da Hora, Matosinhos, Portugal
| | - João Vale
- Department of Pathology, Ipatimup Diagnostics, Institute of Molecular Pathology and Immunology, University of Porto, Rua Júlio Amaral de Carvalho, 45, 4200-135, Porto, Portugal; I3S - Instituto de Investigação e Inovação em Saúde, University of Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal
| | - Catarina Eloy
- Department of Pathology, Ipatimup Diagnostics, Institute of Molecular Pathology and Immunology, University of Porto, Rua Júlio Amaral de Carvalho, 45, 4200-135, Porto, Portugal; I3S - Instituto de Investigação e Inovação em Saúde, University of Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal; Faculty of Medicine, University of Porto, Alameda Prof Hernâni Monteiro, 4200-319, Porto, Portugal
| | - António Polónia
- Department of Pathology, Ipatimup Diagnostics, Institute of Molecular Pathology and Immunology, University of Porto, Rua Júlio Amaral de Carvalho, 45, 4200-135, Porto, Portugal; I3S - Instituto de Investigação e Inovação em Saúde, University of Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal.
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Woo JW, Lee K, Chung YR, Jang MH, Ahn S, Park SY. The updated 2018 American Society of Clinical Oncology/College of American Pathologists guideline on human epidermal growth factor receptor 2 interpretation in breast cancer: comparison with previous guidelines and clinical significance of the proposed in situ hybridization groups. Hum Pathol 2020; 98:10-21. [PMID: 32027910 DOI: 10.1016/j.humpath.2020.01.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 01/06/2020] [Accepted: 01/23/2020] [Indexed: 12/17/2022]
Abstract
The aim of the study was to evaluate the impact of the updated 2018 American Society of Clinical Oncology (ASCO)/College of American Pathologists (CAP) guideline on human epidermal growth factor receptor 2 (HER2) interpretation in breast cancer compared with that of the previous guidelines and also the significance of in situ hybridization (ISH) groups proposed by the updated guideline. HER2 ISH reports and immunohistochemistry (IHC) data from 1,348 invasive breast cancers diagnosed at a single institution were included in this study. HER2 IHC was reassessed using the 2018 guideline, and HER2 ISH status was determined by the 2007, 2013, and 2018 guidelines. When applying the updated guideline, most of the HER2 ISH-equivocal cases as per the previous guidelines were reclassified as ISH negative, and 0.8% of HER2 ISH-positive tumors as per the 2007 guideline and 2.5% of those as per the 2013 guideline were changed to ISH negative. Accordingly, the negative HER2 ISH results significantly increased in the 2018 guideline compared with the 2013 guideline. HER2 ISH-positive tumors in ISH group 3 (HER2/chromosome enumeration probe 17 [CEP17] ratio <2.0 and average HER2 copy number ≥6.0 per cell) were characterized by equivocal HER2 protein expression, CEP17 copy number gain, and low HER2 copy numbers compared with classic HER2 ISH-positive tumors in ISH group 1 (HER2/CEP17 ratio ≥2.0 and average HER2 copy number ≥4.0 per cell). HER2 ISH-negative tumors in ISH group 4 (HER2/CEP17 ratio <2.0 with average HER2 copy number ≥4.0 and < 6.0 per cell) revealed more aggressive clinicopathologic features and poorer clinical outcomes than those in ISH group 5 (HER2/CEP17 ratio <2.0 and average HER2 copy number <4.0 per cell), especially in the hormone receptor-positive subgroup. In conclusion, implementation of the updated 2018 ASCO/CAP guideline leads to a significant increase in HER2 ISH-negative results compared with the 2013 guideline, mainly via reclassification of the ISH-equivocal cases to ISH-negative ones. ISH groups proposed by the updated guideline provide additional information on the clinicopathologic characteristics of the tumors.
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Affiliation(s)
- Ji Won Woo
- Department of Pathology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Gyeonggi, 13620, Republic of Korea
| | - Kyoungyul Lee
- Department of Pathology, Kangwon National University Hospital, Chuncheon, Kangwon, 24289, Republic of Korea
| | - Yul Ri Chung
- Department of Pathology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Gyeonggi, 13620, Republic of Korea
| | - Min Hye Jang
- Department of Pathology, Yeungnam University Medical Center, Daegu, 42415, Republic of Korea
| | - Soomin Ahn
- Department of Pathology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Gyeonggi, 13620, Republic of Korea
| | - So Yeon Park
- Department of Pathology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Gyeonggi, 13620, Republic of Korea.
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Assessing the impact of the 2018 American Society of Clinical Oncology/College of American Pathologists recommendations on human epidermal growth factor receptor 2 testing by fluorescence in situ hybridization in breast carcinoma. Virchows Arch 2019; 476:367-372. [PMID: 31375912 DOI: 10.1007/s00428-019-02636-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 07/13/2019] [Accepted: 07/24/2019] [Indexed: 10/26/2022]
Abstract
The American Society of Clinical Oncology/College of American Pathologists recently updated their recommendations on human epidermal growth factor receptor 2 (HER2) testing by fluorescence in situ hybridization (FISH) in invasive breast cancer, with a focus on the clarification of less common test patterns of ISH. We assessed the impact of the updated ASCO/CAP guidelines on 1044 FISH tested tumors by comparing categorization according to the 2007, 2013, and 2018 ISH classification criteria. The 2013 guidelines increased the number of positive cases (17.4% vs 10.7%) identifying 70 (6.7%) additional patients who met the eligibility criteria for consideration for HER2-targeted therapy compared with the 2007 guidelines. There was a reduction in equivocal tumors (7.7%) with tumors classified as equivocal by the 2007 guidelines (n = 136) redistributed into positive (74, 54.4%) and negative (49, 36.0%) groups. The 2018 guidelines reclassified 10.8% of tumors in our series with a reduction in the number of positive tumors (7.1%). While the proportion of positive tumors (10.2%) was similar to that in 2007 (10.7%), the composition of this group was significantly altered. HER2 equivocal cases, a group which under the 2013 guidelines caused diagnostic and treatment difficulties, were largely eliminated. Our findings suggest that the 2018 update represents a potentially significant change in therapeutic options for a substantial proportion of patients with 2.9% of FISH-positive tumors according to the 2007 and 2013 guidelines now categorized as HER2 negative and, thus, ineligible for HER2-targeted therapy.
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