{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T05:01:17Z","timestamp":1790312477243,"version":"4.1.0"},"reference-count":17,"publisher":"Springer Science and Business Media LLC","issue":"2","license":[{"start":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T00:00:00Z","timestamp":1788220800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0"},{"start":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T00:00:00Z","timestamp":1788912000000},"content-version":"vor","delay-in-days":8,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Breast Cancer Res Treat"],"published-print":{"date-parts":[[2026,9]]},"DOI":"10.1007\/s10549-026-08061-w","type":"journal-article","created":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T06:37:40Z","timestamp":1788935860000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Real-world treatment patterns and clinical outcomes in patients with emerging estrogen receptor 1 (ESR1)-mutated ER+ metastatic breast cancer in the U.S., 2018-2024"],"prefix":"10.1007","volume":"219","author":[{"given":"Jane L.","family":"Meisel","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Clara","family":"Chen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ayush","family":"Kris","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Meng","family":"Ru","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Timothy","family":"Pham","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8307-5267","authenticated-orcid":false,"given":"James","family":"Roose","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,9,9]]},"reference":[{"issue":"3","key":"8061_CR1","doi-asserted-by":"publisher","first-page":"229","DOI":"10.3322\/caac.218342","volume":"74","author":"F Bray","year":"2024","unstructured":"Bray F, Laversanne M, Sung H et al (2024) Global cancer statistics 2022: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA Cancer J Clin 74(3):229\u2013263. https:\/\/doi.org\/10.3322\/caac.218342","journal-title":"CA Cancer J Clin"},{"issue":"26","key":"8061_CR2","doi-asserted-by":"publisher","first-page":"2557","DOI":"10.1056\/NEJMra1307118","volume":"383","author":"HJ Burstein","year":"2020","unstructured":"Burstein HJ (2020) Systemic therapy for estrogen receptor\u2013positive, HER2-negative breast cancer. N Engl J Med 383(26):2557\u20132570. https:\/\/doi.org\/10.1056\/NEJMra1307118","journal-title":"N Engl J Med"},{"issue":"13","key":"8061_CR3","doi-asserted-by":"publisher","first-page":"3114","DOI":"10.1158\/1078-0432.CCR-19-1424","volume":"26","author":"AB Hanker","year":"2020","unstructured":"Hanker AB, Sudhan D, Arteaga CL (2020) Overcoming endocrine resistance in breast cancer as a personalized therapeutic strategy. Clin Cancer Res 26(13):3114\u20133121. https:\/\/doi.org\/10.1158\/1078-0432.CCR-19-1424","journal-title":"Clin Cancer Res"},{"issue":"11","key":"8061_CR4","doi-asserted-by":"publisher","first-page":"2046","DOI":"10.3390\/cancers16112046","volume":"16","author":"SM Pejerrey","year":"2024","unstructured":"Pejerrey SM, Torres AZ, Nair NB et al (2024) ESR1 mutations: a review of the biological and clinical impact on endocrine-resistant breast cancer. Cancers (Basel) 16(11):2046. https:\/\/doi.org\/10.3390\/cancers16112046","journal-title":"Cancers (Basel)"},{"issue":"5","key":"8061_CR5","doi-asserted-by":"publisher","first-page":"673","DOI":"10.1001\/jamaoncol.2024.0307","volume":"10","author":"CJ Kinslow","year":"2024","unstructured":"Kinslow CJ, Wang TJC (2024) ESR1 mutations in metastatic breast cancer. JAMA Oncol 10(5):673\u2013674. https:\/\/doi.org\/10.1001\/jamaoncol.2024.0307","journal-title":"JAMA Oncol"},{"issue":"313","key":"8061_CR6","doi-asserted-by":"publisher","first-page":"313ra182","DOI":"10.1126\/scitranslmed.aac7551","volume":"7","author":"G Schiavon","year":"2015","unstructured":"Schiavon G, Hrebien S, Garcia-Murillas I et al (2015) Analysis of ESR1 mutation in circulating tumor DNA as a prognostic and predictive biomarker in HER2-negative metastatic breast cancer patients. Sci Transl Med 7(313):313ra182. https:\/\/doi.org\/10.1126\/scitranslmed.aac7551","journal-title":"Sci Transl Med"},{"key":"8061_CR7","doi-asserted-by":"publisher","first-page":"11579","DOI":"10.1038\/ncomms11579","volume":"7","author":"JM Spoerke","year":"2016","unstructured":"Spoerke JM, Gendreau S, Walter K et al (2016) Heterogeneity and clinical relevance of ESR1 mutations in metastatic breast cancer patients in ROCOCO. Nat Commun 7:11579. https:\/\/doi.org\/10.1038\/ncomms11579","journal-title":"Nat Commun"},{"issue":"1","key":"8061_CR8","doi-asserted-by":"publisher","first-page":"16","DOI":"10.1186\/s13058-020-1246-5","volume":"22","author":"A Zundelevich","year":"2020","unstructured":"Zundelevich A, Dvir A, Wolf I (2020) ESR1 mutations are frequent in newly diagnosed metastatic and loco-regional recurrence of endocrine-treated breast cancer and carry worse prognosis. Breast Cancer Res 22(1):16. https:\/\/doi.org\/10.1186\/s13058-020-1246-5","journal-title":"Breast Cancer Res"},{"issue":"11","key":"8061_CR9","doi-asserted-by":"publisher","first-page":"2752","DOI":"10.1210\/clinem\/dgad236","volume":"108","author":"N Chaudhary","year":"2023","unstructured":"Chaudhary N, Jeselsohn R (2023) ESR1 mutations in breast cancer: basic mechanisms and clinical implications. J Clin Endocrinol Metab 108(11):2752\u20132761. https:\/\/doi.org\/10.1210\/clinem\/dgad236","journal-title":"J Clin Endocrinol Metab"},{"issue":"25","key":"8061_CR10","doi-asserted-by":"publisher","first-page":"2961","DOI":"10.1200\/JCO.2016.67.3061","volume":"34","author":"C Fribbens","year":"2016","unstructured":"Fribbens C, O\u2019Leary B, Kilburn L et al (2016) Plasma ESR1 mutations and the treatment of metastatic breast cancer with fulvestrant: results from the SoFEA trial. J Clin Oncol 34(25):2961\u20132968. https:\/\/doi.org\/10.1200\/JCO.2016.67.3061","journal-title":"J Clin Oncol"},{"issue":"11","key":"8061_CR11","doi-asserted-by":"publisher","first-page":"1367","DOI":"10.1016\/S1470-2045(22)00555-4","volume":"23","author":"FC Bidard","year":"2022","unstructured":"Bidard FC, Hardy-Bessard AC, Dalenc F et al (2022) Switch to fulvestrant and palbociclib versus no switch in advanced breast cancer with rising ESR1 mutation during first-line aromatase inhibitor (PADA-1): a randomised, open-label, multicentre, phase 3 trial. Lancet Oncol 23(11):1367\u20131377. https:\/\/doi.org\/10.1016\/S1470-2045(22)00555-4","journal-title":"Lancet Oncol"},{"issue":"6","key":"8061_CR12","doi-asserted-by":"publisher","first-page":"569","DOI":"10.1056\/NEJMoa2502929","volume":"393","author":"FC Bidard","year":"2025","unstructured":"Bidard FC, Mayer EL, Park YH, SERENA-6 Study Group et al (2025) First-line camizestrant for emerging ESR1-mutated advanced breast cancer. N Engl J Med 393(6):569\u2013580. https:\/\/doi.org\/10.1056\/NEJMoa2502929","journal-title":"N Engl J Med"},{"key":"8061_CR13","unstructured":"Ministry of Health NZ. Annual update of key results 2023\/24: New Zealand Health Survey. Published November 19 (2024) Accessed March 20, 2025. https:\/\/www.health.govt.nz\/publications\/annual-update-of-key-results-202324-new-zealand-health-survey."},{"key":"8061_CR14","unstructured":"R Core Team (2024) R: a language and environment for statistical computing. R Foundation for Statistical Computing. https:\/\/www.R-project.org\/. Accessed March 20, 2025"},{"issue":"11","key":"8061_CR15","doi-asserted-by":"publisher","first-page":"2046","DOI":"10.3390\/cancers16112046","volume":"16","author":"AZ Torres","year":"2024","unstructured":"Torres AZ, Pejerrey SM, Nair NB et al (2024) ESR1 mutations: a review of the biological and clinical impact on endocrine-resistant breast cancer. Cancers (Basel) 16(11):2046. https:\/\/doi.org\/10.3390\/cancers16112046","journal-title":"Cancers (Basel)"},{"issue":"7","key":"8061_CR16","doi-asserted-by":"publisher","first-page":"1757","DOI":"10.1158\/1078-0432.CCR-13-2332","volume":"20","author":"R Jeselsohn","year":"2014","unstructured":"Jeselsohn R, Yelensky R, Buchwalter G et al (2014) Emergence of constitutively active estrogen receptor-\u03b1 mutations in pretreated advanced estrogen receptor\u2013positive breast cancer. Clin Cancer Res 20(7):1757\u20131767. https:\/\/doi.org\/10.1158\/1078-0432.CCR-13-2332","journal-title":"Clin Cancer Res"},{"issue":"1","key":"8061_CR17","doi-asserted-by":"publisher","first-page":"16","DOI":"10.1186\/s13058-020-1246-5","volume":"22","author":"A Zundelevich","year":"2020","unstructured":"Zundelevich A, Dadiani M, Kahana-Edwin S et al (2020) ESR1 mutations are frequent in newly diagnosed metastatic and loco-regional recurrence of endocrine-treated breast cancer and carry worse prognosis. Breast Cancer Res 22(1):16. https:\/\/doi.org\/10.1186\/s13058-020-1246-5","journal-title":"Breast Cancer Res"}],"container-title":["Breast Cancer Research and Treatment"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s10549-026-08061-w.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s10549-026-08061-w","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s10549-026-08061-w.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T04:54:26Z","timestamp":1790312066000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s10549-026-08061-w"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,9]]},"references-count":17,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2026,9]]}},"alternative-id":["8061"],"URL":"https:\/\/doi.org\/10.1007\/s10549-026-08061-w","relation":{},"ISSN":["0167-6806","1573-7217"],"issn-type":[{"value":"0167-6806","type":"print"},{"value":"1573-7217","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,9]]},"assertion":[{"value":"16 June 2026","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"14 August 2026","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"9 September 2026","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"Not applicable.","order":1,"name":"Ethics","label":"Ethical approval","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"SABCS 2025.","order":2,"name":"Ethics","label":"Prior disclosures of these data","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"The data that support the findings of this study were originated by and are the property of Flatiron Health, Inc. Requests for data sharing by license or by permission for the specific purpose of replicating results in this manuscript can be submitted to PublicationsDataAccess@flatiron.com.","order":3,"name":"Ethics","label":"Data access statement","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"James Roose is employed by Flatiron Health, Inc., an independent member of the Roche Group, and owns stock in Roche. Ayush Kris is employed by Flatiron Health, Inc., an independent member of the Roche Group. Timothy Pham was employed by AstraZeneca at the time of this study. Clara Chen is employed by AstraZeneca. Meng Ru is employed by AstraZeneca. Jane Meisel has served in a consulting or advisory role for Novartis, AstraZeneca, Genentech, Seagen, Olema Oncology, GE Healthcare, Pfizer, Stemline Therapeutics, and Sermonix Pharmaceuticals, and has received institutional research funding from Pfizer, Seagen, Sermonix Pharmaceuticals, Olema Oncology, and AstraZeneca.","order":4,"name":"Ethics","label":"Competing interests","group":{"name":"EthicsHeading","label":"Declarations"}}],"article-number":"9"}}