{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,13]],"date-time":"2026-02-13T14:21:52Z","timestamp":1770992512899,"version":"3.50.1"},"reference-count":20,"publisher":"Oxford University Press (OUP)","issue":"2","license":[{"start":{"date-parts":[[2025,11,21]],"date-time":"2025-11-21T00:00:00Z","timestamp":1763683200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,2,13]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Anthracycline (A) and taxane (T)-based therapies improve breast cancer survival, with guidelines strongly recommending these regimens and dose-dense approaches. However, the real-world maintenance of optimal dose intensity, a critical prognostic factor, remains unclear. We aimed to clarify the current treatment situation regarding relative dose intensity (RDI), with a secondary focus on safety.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>In this retrospective observational study, we analyzed big data from the DATuM IDEA\u00ae electronic medical record database of the Japan Medical Association Medical Information Management Organization, collected from 1\u2009206\u2009955 individuals across 53 medical institutions throughout Japan over 57\u00a0months since 2019. We focused on women with primary breast cancer receiving adriamycin\/cyclophosphamide (AC), epirubicin\/cyclophosphamide (EC), or docetaxel\/cyclophosphamide chemotherapy (TC).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Analysis included 1989 women who received at least two courses of AC, EC, or TC perioperatively. Patients received 2-weekly adriamycin\/cyclophosphamide (ddAC) (n\u00a0=\u00a0207), 3-weekly AC (AC q3w) (n\u00a0=\u00a0177), 2-weekly epirubicin\/cyclophosphamide (ddEC) (n\u00a0=\u00a0269), 3-weekly EC (EC q3w) (n\u00a0=\u00a0684), and TC (n\u00a0=\u00a0652). Pegfilgrastim was administered to 98% of ddAC\/ddEC, 38% of AC q3w, 42% of EC q3w, and 74% of TC patients. Grade 4 neutropenia (incidences &amp;gt;20%) was observed in AC q3w patients aged \u226565\u00a0years (22.6%) and in TC patients of any age (27.6%). RDI remained &amp;gt;95% in all groups.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>RDI was high in all groups. Clinicians should be cautious when administering AC q3w therapy owing to the high likelihood of patients developing Grade 4 neutropenia. For TC, a slightly lower pegfilgrastim administration rate and\u00a0&amp;gt;20% Grade 4 neutropenia suggest the need for appropriate pegfilgrastim use.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/jjco\/hyaf177","type":"journal-article","created":{"date-parts":[[2025,11,21]],"date-time":"2025-11-21T15:12:18Z","timestamp":1763737938000},"page":"130-138","source":"Crossref","is-referenced-by-count":0,"title":["Real-world outcomes of anthracycline and taxane-based perioperative breast cancer therapy using the Japanese electronic medical record database"],"prefix":"10.1093","volume":"56","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1383-0487","authenticated-orcid":false,"given":"Masaaki","family":"Kawai","sequence":"first","affiliation":[{"name":"Department of Surgery I, Yamagata University Graduate School of Medical Science , 2-2-2, Iida-nishi, Yamagata, Yamagata, 990-9575 ,","place":["Japan"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tomoko","family":"Kazato","sequence":"additional","affiliation":[{"name":"TOPPAN Holdings Inc. \u00a0 1-3-3, Suido, Bunkyo-ku, Tokyo, 112-8531 ,","place":["Japan"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wakana","family":"Kiyosaki","sequence":"additional","affiliation":[{"name":"TOPPAN Holdings Inc. \u00a0 1-3-3, Suido, Bunkyo-ku, Tokyo, 112-8531 ,","place":["Japan"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shigeru","family":"Matsuura","sequence":"additional","affiliation":[{"name":"TOPPAN Holdings Inc. \u00a0 1-3-3, Suido, Bunkyo-ku, Tokyo, 112-8531 ,","place":["Japan"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7601-8395","authenticated-orcid":false,"given":"Fuyuhiko","family":"Motoi","sequence":"additional","affiliation":[{"name":"Department of Surgery I, Yamagata University Graduate School of Medical Science , 2-2-2, Iida-nishi, Yamagata, Yamagata, 990-9575 ,","place":["Japan"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"286","published-online":{"date-parts":[[2025,11,21]]},"reference":[{"key":"2026021308522388200_ref1","doi-asserted-by":"publisher","first-page":"CD004421","DOI":"10.1002\/14651858.CD004421.pub3","article-title":"Taxanes for adjuvant treatment of early breast cancer","volume":"9","author":"Willson","year":"2019","journal-title":"Cochrane Database Syst Rev"},{"key":"2026021308522388200_ref2","doi-asserted-by":"publisher","first-page":"27","DOI":"10.1007\/s10549-018-5055-9","article-title":"Anthracycline and taxane-based chemotherapy versus docetaxel and cyclophosphamide in the adjuvant treatment of HER2-negative breast cancer patients: a systematic review and meta-analysis of randomized controlled trials","volume":"174","author":"Caparica","year":"2019","journal-title":"Breast Cancer Res 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