{
  "abstract": "Some patients with HER2-positive metastatic breast cancer (MBC) achieve prolonged disease control with first-line anti-HER2-based therapy, but associated clinical features remain poorly characterized in real-world populations. We conducted a retrospective study using the Epidemiological Strategy and Medical Economics (ESME) MBC cohort, including 18 French comprehensive cancer centers. Women with HER2-positive MBC who initiated first-line anti-HER2-based therapy between January 2008 and December 2021 and had at least 3 years of follow-up were eligible. Exceptional responders had no documented progression within 3 years. A secondary analysis evaluated factors associated with remaining progression-free at 5 years. Multivariable logistic regression with bootstrap cross-validation was used. Among 4307 eligible patients, 1016 (23.6%) were exceptional responders. Of 765 evaluable at 5 years, 523 (68.4%) remained progression-free. Factors associated with a lower likelihood of exceptional response included hormone receptor-negative (HR-) disease, a disease-free interval of 6-24 months, ≥3 metastatic sites, visceral metastases, and central nervous system involvement. First-line treatment with chemotherapy, trastuzumab, and pertuzumab was associated with exceptional response. Among exceptional responders, HR-disease, grade III tumors and first-line chemotherapy plus trastuzumab and pertuzumab were associated with progression-free at 5-year, whereas visceral metastases were associated with lower odds. Model discrimination was moderate (AUC 0.72 and 0.64, respectively). Nearly one quarter of patients remained progression-free for at least 3 years, and more than two thirds of those evaluable remained progression-free at 5 years. Clinical variables alone had limited predictive value, supporting the need for molecular and immune biomarkers to better identify this subgroup.",
  "abstract_shown": true,
  "affiliations": [
    "Medical Oncology Department, Institut Gustave Roussy, Villejuif, France; Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA, USA. Electronic address: thomas.grinda@gustaveroussy.fr.",
    "Department of Biostatistics, Institut Curie, Saint-Cloud, France.",
    "Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA, USA.",
    "Medical Oncology Department, Centre Oscar Lambret, Lille, France.",
    "Medical Oncology Department, Centre Francois Baclesse, Caen, France.",
    "Medical Oncology Department, Institut de Cancérologie Strasbourg Europe ICANS, Strasbourg, France.",
    "Medical Oncology Department, Centre Léon Bérard, Lyon, France.",
    "Medical Oncology Department, Institute Bergonié, Bordeaux, France.",
    "Medical Oncology Department, Centre Eugene Marquis, Rennes, France.",
    "Medical Oncology Department, Institut de cancérologie de Lorraine, Vandoeuvre Les Nancy, France.",
    "Medical Oncology Department, Oncopole Claudius Regaud, IUCT, Toulouse, France.",
    "Medical Oncology Department, Centre Georges François Leclerc, Dijon, France.",
    "Department of Medical Oncology, Institut Curie, Paris, France.",
    "Medical Oncology Department, Institut Paoli Calmettes, Marseille, France.",
    "Medical Oncology Department, Centre Antoine Lacassagne, Nice, France.",
    "Medical Oncology Department, Institut de Cancerologie de l'Ouest René Gauducheau, Saint-Herblain, France.",
    "Health Data and Partnerships Department, Unicancer, Paris, France.",
    "Medical Oncology Department, Institut du cancer de Montpellier, INSERM U1194, Montpellier University, Montpellier, France."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 20,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Thomas Grinda",
      "orcid": "0000-0002-8567-9627"
    },
    {
      "affs": [
        1
      ],
      "name": "Matthieu Carton",
      "orcid": "0000-0002-6793-3273"
    },
    {
      "affs": [
        2
      ],
      "name": "Stefania Morganti"
    },
    {
      "affs": [
        3
      ],
      "name": "Audrey Mailliez"
    },
    {
      "affs": [
        4
      ],
      "name": "Christelle Levy"
    },
    {
      "affs": [
        5
      ],
      "name": "Thierry Petit"
    },
    {
      "affs": [
        6
      ],
      "name": "Thomas Bachelot",
      "orcid": "0000-0002-0866-9484"
    },
    {
      "affs": [
        7
      ],
      "name": "Monica Arnedos",
      "orcid": "0000-0001-5269-1251"
    },
    {
      "affs": [
        8
      ],
      "name": "Véronique Diéras",
      "orcid": "0000-0001-8094-4738"
    },
    {
      "affs": [
        9
      ],
      "name": "Vincent Massard",
      "orcid": "0009-0007-6690-3535"
    },
    {
      "affs": [
        10
      ],
      "name": "Florence Dalenc"
    },
    {
      "affs": [
        11
      ],
      "name": "Isabelle Desmoulins"
    },
    {
      "affs": [
        12
      ],
      "name": "Jean-Yves Pierga"
    },
    {
      "affs": [
        13
      ],
      "name": "Anthony Gonçalves"
    },
    {
      "affs": [
        14
      ],
      "name": "Caroline Bailleux"
    },
    {
      "affs": [
        15
      ],
      "name": "Jean-Sebastien Frenel"
    },
    {
      "affs": [
        16
      ],
      "name": "Lise Bosquet"
    },
    {
      "affs": [
        2
      ],
      "name": "Heather A Parsons"
    },
    {
      "affs": [
        17
      ],
      "name": "William Jacot"
    },
    {
      "affs": [
        2
      ],
      "name": "Nancy U Lin"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/6zw3r040x2c9m.bib",
  "cited_by": 0,
  "doi": "10.1016/j.breast.2026.104943",
  "fulltext_url": "https://europepmc.org/articles/PMC13693059",
  "id": "6zw3r040x2c9m",
  "issns": [
    "0960-9776",
    "1532-3080"
  ],
  "landing_url": "https://europepmc.org/article/MED/42880095",
  "language": "eng",
  "licence": "CC-BY-NC-ND",
  "licence_label": "CC BY-NC-ND",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "2730|HER2/EGFR in Cancer Research"
    ]
  ],
  "openalex": "W7221596744",
  "pdf_url": "https://europepmc.org/articles/PMC13693059?pdf=render",
  "pmcid": "PMC13693059",
  "pmid": "42880095",
  "published": "2026-10-13",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/6zw3r040x2c9m.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:00Z",
      "native_id": "MED:42880095",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42880095"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2730|HER2/EGFR in Cancer Research",
      "subfield": "oncology"
    }
  ],
  "title": "Clinical features associated with exceptional response on first-line anti-HER2-based therapy for metastatic breast cancer: real-world data from the ESME national cohort.",
  "title_text": "Clinical features associated with exceptional response on first-line anti-HER2-based therapy for metastatic breast cancer: real-world data from the ESME national cohort.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:19:00Z",
  "url": "https://research.draconitic.com/paper/6zw3r040x2c9m",
  "venue": "Breast (Edinburgh, Scotland)",
  "versions": []
}