ESMO expert consensus statements (ECS) on the definition, diagnosis, and management of HER2-low breast cancer

P Tarantino; G Viale; M F Press; X Hu; F Penault-Llorca; A Bardia; A Batistatou; H J Burstein; L A Carey; J Cortes; C Denkert; V Diéras; W Jacot; A K Koutras; A Lebeau; S Loibl; S Modi; M F Mosele; E Provenzano; G Pruneri; J S Reis-Filho; F Rojo; R Salgado; P Schmid; S J Schnitt; S M Tolaney; D Trapani; A Vincent-Salomon; A C Wolff; G Pentheroudakis; F André; G Curigliano

doi:10.1016/j.annonc.2023.05.008

ESMO expert consensus statements (ECS) on the definition, diagnosis, and management of HER2-low breast cancer

Ann Oncol. 2023 Aug;34(8):645-659. doi: 10.1016/j.annonc.2023.05.008. Epub 2023 Jun 1.

Authors

P Tarantino¹, G Viale², M F Press³, X Hu⁴, F Penault-Llorca⁵, A Bardia⁶, A Batistatou⁷, H J Burstein⁸, L A Carey⁹, J Cortes¹⁰, C Denkert¹¹, V Diéras¹², W Jacot¹³, A K Koutras¹⁴, A Lebeau¹⁵, S Loibl¹⁶, S Modi¹⁷, M F Mosele¹⁸, E Provenzano¹⁹, G Pruneri²⁰, J S Reis-Filho²¹, F Rojo²², R Salgado²³, P Schmid²⁴, S J Schnitt²⁵, S M Tolaney⁸, D Trapani²⁶, A Vincent-Salomon²⁷, A C Wolff²⁸, G Pentheroudakis²⁹, F André³⁰, G Curigliano³¹

Affiliations

¹ Department of Medical Oncology, Dana-Farber Cancer Institute, Boston; Harvard Medical School, Boston, USA; Department of Oncology and Hemato-Oncology, University of Milan, Milan.
² Department of Pathology and Laboratory Medicine, European Institute of Oncology IRCCS, Milan, Italy.
³ Department of Pathology, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, USA.
⁴ Department of Medical Oncology, Shanghai Cancer Center, Fudan University, Shanghai, China.
⁵ Centre de Lutte Contre le Cancer Centre Jean PERRIN, Clermont-Ferrand, France.
⁶ Harvard Medical School, Boston, USA; Department of Medical Oncology, Massachusetts General Hospital, Boston, USA.
⁷ Department of Pathology, Faculty of Medicine, University of Ioannina, Ioannina, Greece.
⁸ Department of Medical Oncology, Dana-Farber Cancer Institute, Boston; Harvard Medical School, Boston, USA.
⁹ Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, USA.
¹⁰ International Breast Cancer Center (IBCC), Pangaea Oncology, Quironsalud Group, Barcelona; Faculty of Biomedical and Health Sciences, Department of Medicine, Universidad Europea de Madrid, Madrid, Spain.
¹¹ Philipps-University Marburg and University Hospital Marburg (UKGM), Marburg, Germany.
¹² Department of Medical Oncology, Centre Eugène Marquis, Rennes.
¹³ Department of Medical Oncology, Institut du Cancer de Montpellier, Montpellier University, INSERM U1194, Montpellier, France.
¹⁴ Division of Oncology, Department of Medicine, University Hospital of Patras, Greece.
¹⁵ Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg.
¹⁶ German Breast Group/GBG Forschungs GmbH, Neu-Isenburg; Goethe University Frankfurt, Frankfurt, Germany.
¹⁷ Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, USA.
¹⁸ Department of Medical Oncology, Institute Gustave Roussy, Villejuif, France.
¹⁹ Department of Histopathology, Cambridge University NHS Foundation Trust and NIH Cambridge Biomedical Research Centre, Cambridge, UK.
²⁰ Department of Oncology and Hemato-Oncology, University of Milan, Milan; Department of Advanced Diagnostics, Fondazione IRCCS Istituto Nazionale Tumori, Milan, Italy.
²¹ Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, USA.
²² Department of Pathology, IIS-Fundacion Jimenez Diaz University Hospital-CIBERONC, Madrid, Spain.
²³ Department of Pathology, ZAS, Antwerp, Belgium; Division of Research, Peter Mac Callum Cancer Centre, Melbourne, Australia.
²⁴ Barts Cancer Institute, Queen Mary University London, London, UK.
²⁵ Harvard Medical School, Boston, USA; Department of Pathology, Brigham and Women's Hospital and Breast Oncology Program, Dana-Farber Cancer Institute, Boston, USA.
²⁶ Department of Oncology and Hemato-Oncology, University of Milan, Milan; European Institute of Oncology, IRCCS, Milan, Italy.
²⁷ Department of Pathology, Diagnostic and Theranostic Medicine Division, Institut Curie, PSL University, Paris, France.
²⁸ The Johns Hopkins Sidney Kimmel Comprehensive Cancer Center, Baltimore, USA.
²⁹ European Society for Medical Oncology, Lugano, Switzerland.
³⁰ INSERM U981 - Molecular Predictors and New Targets in Oncology, PRISM Center for Precision Medicine, Gustave Roussy, Villejuif, France.
³¹ Department of Oncology and Hemato-Oncology, University of Milan, Milan; European Institute of Oncology, IRCCS, Milan, Italy. Electronic address: [email protected].

PMID: 37269905
DOI: 10.1016/j.annonc.2023.05.008

Abstract

Human epidermal growth factor receptor 2 (HER2)-low breast cancer has recently emerged as a targetable subset of breast tumors, based on the evidence from clinical trials of novel anti-HER2 antibody-drug conjugates. This evolution has raised several biological and clinical questions, warranting the establishment of consensus to optimally treat patients with HER2-low breast tumors. Between 2022 and 2023, the European Society for Medical Oncology (ESMO) held a virtual consensus-building process focused on HER2-low breast cancer. The consensus included a multidisciplinary panel of 32 leading experts in the management of breast cancer from nine different countries. The aim of the consensus was to develop statements on topics that are not covered in detail in the current ESMO Clinical Practice Guideline. The main topics identified for discussion were (i) biology of HER2-low breast cancer; (ii) pathologic diagnosis of HER2-low breast cancer; (iii) clinical management of HER2-low metastatic breast cancer; and (iv) clinical trial design for HER2-low breast cancer. The expert panel was divided into four working groups to address questions relating to one of the four topics outlined above. A review of the relevant scientific literature was conducted in advance. Consensus statements were developed by the working groups and then presented to the entire panel for further discussion and amendment before voting. This article presents the developed statements, including findings from the expert panel discussions, expert opinion, and a summary of evidence supporting each statement.

Keywords: HER2-low; antibody–drug conjugates; breast cancer; consensus.

Publication types

Review
Practice Guideline

MeSH terms

Breast Neoplasms* / diagnosis
Breast Neoplasms* / drug therapy
Consensus
Female
Humans
Medical Oncology