イワモト　タカユキ   Takayuki Iwamoto   岩本　高行    所属   川崎医科大学  医学部 臨床医学　乳腺甲状腺外科学    職種   講師
論文種別	原著
言語種別	英語
査読の有無	査読あり
表題	The efficacy of sequential second-line endocrine therapies (ETs) in postmenopausal estrogen receptor-positive and HER2-negative metastatic breast cancer patients with lower sensitivity to initial ETs.
掲載誌名	正式名：Breast cancer (Tokyo, Japan) 略　 称：Breast Cancer ISSNコード：18804233/13406868
掲載区分	国外
巻・号・頁	27(5),pp.973-981
著者・共著者	Takayuki Iwamoto, Tomomi Fujisawa, Tadahiko Shien, Kazuhiro Araki, Kentaro Sakamaki, Takafumi Sangai, Yuichiro Kikawa, Shintaro Takao, Reiki Nishimura, Masato Takahashi, Tomohiko Aihara, Hirofumi Mukai, Naruto Taira
担当区分	筆頭著者,責任著者
発行年月	2020/09
概要	PURPOSE:Second-line endocrine therapy (ET) for estrogen receptor (ER)-positive and human epidermal growth factor 2 (HER2)-negative metastatic breast cancer (MBC) is offered based on the response to first-line ET. However, no clinical trials have evaluated the efficacy and safety of secondary ETs in patients with poor responses to initial ET. This study evaluated the efficacy of second-line ET in ER-positive and HER2-negative postmenopausal MBC patients with low or very low sensitivity to initial ET.METHODS:This multicenter prospective observational cohort study evaluated the response of 49 patients to second-line ETs in postmenopausal MBC patients with low or very low sensitivity to initial ET. The primary endpoint was the clinical benefit rate (CBR) for 24 weeks.RESULTS:Of the 49 patients assessed, 40 (82%) received fulvestrant in the second line, 5 (10%) received selective estrogen receptor modulators, 3 (6%) received aromatase inhibitors (AIs) alone, and 1 received everolimus with a steroidal AI. The overall CBR was 44.9% [90% confidence interval (CI): 34.6-57.6, p = 0.009]; CBR demonstrated similar significance across the progesterone receptor-positive (n = 39, 51.3%, 90% CI: 39.6-65.2, p = 0.002), very low sensitivity (n = 17, 58.8%, 90% CI: 42.0-78.8, p = 0.003), and non-visceral metastases (n = 25, 48.0%, 90% CI: 34.1-65.9, p = 0.018) groups. The median progression-free survival was 7.1 months (95% CI: 5.6-10.6).CONCLUSION:Second-line ET might be a viable treatment option for postmenopausal patients with MBC with low and very low sensitivity to initial ET. Future studies based on larger and independent cohorts are needed to validate these findings.
DOI	10.1007/s12282-020-01095-y
PMID	32394413