{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,19]],"date-time":"2025-12-19T08:41:41Z","timestamp":1766133701291,"version":"3.48.0"},"reference-count":24,"publisher":"Oxford University Press (OUP)","issue":"12","license":[{"start":{"date-parts":[[2025,12,5]],"date-time":"2025-12-05T00:00:00Z","timestamp":1764892800000},"content-version":"vor","delay-in-days":4,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["82172578"],"award-info":[{"award-number":["82172578"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["82473943"],"award-info":[{"award-number":["82473943"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["81702676"],"award-info":[{"award-number":["81702676"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,12,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Background: Limited data are available on estradiol (E2) levels during fulvestrant treatment in women with hormone receptor-positive breast cancer.<\/jats:p>\n                  <jats:p>Methods: We measured plasma E2 levels in women receiving fulvestrant using liquid chromatography\u2013tandem mass spectrometry. Patient characteristics and treatment efficacy were assessed in relation to E2 levels. A cutoff of 2.72\u2009pg\/mL was used because it defines E2 suppression and postmenopausal status.<\/jats:p>\n                  <jats:p>Results: A total of 69 women were enrolled, with a median age of 48\u2009years. The median duration of fulvestrant treatment was 11.6\u2009months. The median E2 level across the cohort was 3.60\u2009pg\/mL, with considerable interindividual variability (range: 1.11-526.13\u2009pg\/mL), and 49 women (71.0%) had E2 levels above 2.72\u2009pg\/mL. Eleven women (15.9%) had premenopausal E2 levels (&amp;gt;10\u2009pg\/mL). During a median follow-up period of 8.4\u2009months, there was no statistically significant difference in progression-free survival (PFS) between women with E2 levels &amp;gt;2.72\u2009pg\/mL and those with E2 levels \u22642.72\u2009pg\/mL (P\u2009=\u2009.391). However, among women who benefited from first- or second-line fulvestrant therapy (PFS &amp;gt; 6\u2009months), those with E2 levels &amp;gt;2.72\u2009pg\/mL exhibited significantly poorer PFS compared to those with E2 levels \u22642.72\u2009pg\/mL (P\u2009=\u2009.043).<\/jats:p>\n                  <jats:p>Conclusions: These findings support the need for E2 monitoring in women receiving fulvestrant therapy to better assess E2 status and its association with treatment efficacy.<\/jats:p>","DOI":"10.1093\/oncolo\/oyaf403","type":"journal-article","created":{"date-parts":[[2025,12,4]],"date-time":"2025-12-04T13:20:05Z","timestamp":1764854405000},"source":"Crossref","is-referenced-by-count":0,"title":["Estradiol levels in women with hormone receptor-positive advanced breast cancer on fulvestrant therapy"],"prefix":"10.1093","volume":"30","author":[{"given":"Shuqin","family":"Dai","sequence":"first","affiliation":[{"name":"Department of Medicine Laboratory, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yanling","family":"Wen","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xingping","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Medicine Laboratory, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xi","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Breast Oncology, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhongyu","family":"Yuan","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8543-6636","authenticated-orcid":false,"given":"Fei","family":"Xu","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaoming","family":"Xie","sequence":"additional","affiliation":[{"name":"Department of Breast Oncology, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wen","family":"Xia","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shusen","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5414-8049","authenticated-orcid":false,"given":"Yanxia","family":"Shi","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Peng","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Breast Oncology, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qiufan","family":"Zheng","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jun","family":"Tang","sequence":"additional","affiliation":[{"name":"Department of Breast Oncology, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xin","family":"An","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jiajia","family":"Huang","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7195-1300","authenticated-orcid":false,"given":"Meiting","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yongyi","family":"Zhong","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiwen","family":"Bi","sequence":"additional","affiliation":[{"name":"Department of Medical Oncology, State Key Laboratory of Oncology in South China, Guangdong Provincial Clinical Research Center for Cancer, Sun Yat-Sen University Cancer Center , Guangzhou 510060,","place":["P. R. China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yi","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-Sen University , Guangzhou 510080,","place":["P. R. 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young breast cancer patients","volume":"117","author":"Lambertini","year":"2025","journal-title":"J Natl Cancer Inst"},{"key":"2025121903362675300_oyaf403-B20","doi-asserted-by":"crossref","DOI":"10.1093\/jnci\/djx074","article-title":"Ovarian function recovery during anastrozole in breast cancer patients with chemotherapy-induced ovarian function failure","volume":"109","author":"van Hellemond","year":"2017","journal-title":"J Natl Cancer Inst"},{"key":"2025121903362675300_oyaf403-B21","doi-asserted-by":"crossref","first-page":"103818","DOI":"10.1016\/j.breast.2024.103818","article-title":"Clinical significance of serum estradiol monitoring in women receiving adjuvant aromatase inhibitor for hormone receptor-positive early breast cancer","volume":"78","author":"Dai","year":"2024","journal-title":"Breast"},{"key":"2025121903362675300_oyaf403-B22","doi-asserted-by":"crossref","first-page":"147","DOI":"10.1186\/s13058-025-01979-x","article-title":"Evaluation and management of incomplete 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