{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T17:03:00Z","timestamp":1780592580582,"version":"3.54.1"},"reference-count":34,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,2,12]],"date-time":"2022-02-12T00:00:00Z","timestamp":1644624000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100004319","name":"Pfizer","doi-asserted-by":"publisher","award":["No grant number"],"award-info":[{"award-number":["No grant number"]}],"id":[{"id":"10.13039\/100004319","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Current Oncology"],"abstract":"<jats:p>This retrospective single-arm study assessed real-world treatment patterns and clinical outcomes in patients with hormone receptor\u2014positive\/human epidermal growth factor receptor 2\u2014negative (HR+\/HER2\u2212) advanced\/metastatic breast cancer (A\/MBC) who received palbociclib plus an aromatase inhibitor as first-line therapy in US community health systems. Using electronic health records from the Syapse Learning Health Network, 242 patients were identified as having received first-line palbociclib plus an aromatase inhibitor between 3 February 2015, and 31 July 2019 (data cutoff 1 February 2020) resulting in a minimum potential 6-month follow-up period. In total, 56.6% of patients had de novo A\/MBC at initial breast cancer diagnosis, 50.8% had bone-only disease, and 32.2% had visceral disease. Median follow-up was 22.4 months. Disease progression (26.4%) and intolerance\/toxicity (14.9%) were the main reasons for treatment discontinuation. The median (95% CI) real-world progression-free survival was 31.7 (27.9\u2014not estimable (NE)) months and 2-year estimated overall survival (OS) rate was 78.0%. In total, 25.6% of patients died; however, OS data are limited by the small population size and insufficient follow-up time. These real-world effectiveness outcomes complement findings from other real-world studies and randomized controlled trials and support palbociclib plus an aromatase inhibitor as first-line therapy for HR+\/HER2\u2212 A\/MBC.<\/jats:p>","DOI":"10.3390\/curroncol29020089","type":"journal-article","created":{"date-parts":[[2022,2,13]],"date-time":"2022-02-13T20:32:30Z","timestamp":1644784350000},"page":"1047-1061","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Real-World Treatment Patterns and Clinical Effectiveness of Palbociclib Plus an Aromatase Inhibitor as First-Line Therapy in Advanced\/Metastatic Breast Cancer: Analysis from the US Syapse Learning Health Network"],"prefix":"10.3390","volume":"29","author":[{"given":"Jeanna Wallenta","family":"Law","sequence":"first","affiliation":[{"name":"Syapse, San Francisco, CA 94107, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Debanjali","family":"Mitra","sequence":"additional","affiliation":[{"name":"Pfizer Inc., New York, NY 10017, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Henry G.","family":"Kaplan","sequence":"additional","affiliation":[{"name":"Swedish Cancer Institute, Seattle, WA 98104, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tamuno","family":"Alfred","sequence":"additional","affiliation":[{"name":"Pfizer Inc., New York, NY 10017, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8080-7960","authenticated-orcid":false,"given":"Adam M.","family":"Brufsky","sequence":"additional","affiliation":[{"name":"Comprehensive Breast Cancer Center, University of Pittsburgh Medical Center, Pittsburgh, PA 15213, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Birol","family":"Emir","sequence":"additional","affiliation":[{"name":"Pfizer Inc., New York, NY 10017, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haley","family":"McCracken","sequence":"additional","affiliation":[{"name":"Syapse, San Francisco, CA 94107, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xianchen","family":"Liu","sequence":"additional","affiliation":[{"name":"Pfizer Inc., New York, NY 10017, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ronda G.","family":"Broome","sequence":"additional","affiliation":[{"name":"Syapse, San Francisco, CA 94107, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1773-4441","authenticated-orcid":false,"given":"Chenan","family":"Zhang","sequence":"additional","affiliation":[{"name":"Syapse, San Francisco, CA 94107, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2317-5976","authenticated-orcid":false,"given":"Caroline","family":"DiCristo","sequence":"additional","affiliation":[{"name":"Pfizer Inc., New York, NY 10017, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Connie","family":"Chen","sequence":"additional","affiliation":[{"name":"Pfizer Inc., New York, NY 10017, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,2,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7","DOI":"10.3322\/caac.21708","article-title":"Cancer statistics, 2022","volume":"72","author":"Siegel","year":"2022","journal-title":"CA Cancer J. 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