Iino Y, Maemura M, Morishita Y
Department of Emergency and Critical Care Medicine, Gunma University School of Medicine.
Nihon Rinsho. 1997 May;55(5):1149-54.
Although non-steroidal antiestrogen, tamoxifen(TAM), has been known to be useful for estrogen receptor(ER)-positive breast cancer, acquired tamoxifen resistance frequently occurs during the treatment. Several factors seem to be responsible for the resistance; decreased level of ER, mutation of ER, agonistic effect of TAM, ovarian steroidogenesis, altered metabolism of TAM, and increased expression level of antiestrogen binding sites. Withdrawal of TAM and second-line endocrine therapy might be effective on the tamoxifen resistant breast cancer which retains estrogen dependency. Otherwise, chemotherapy should be chosen for estrogen-independent breast cancer which has lost ER and fails to respond to other endocrine therapy. In this context, the menstrual status, serum level of estradiol, and steroid receptor status should be considered for the management of acquired antiestrogen resistance in breast cancer.
尽管非甾体类抗雌激素药物他莫昔芬（TAM）已被证实对雌激素受体（ER）阳性乳腺癌有效，但在治疗过程中常出现获得性他莫昔芬耐药。耐药似乎由多种因素导致，包括ER水平降低、ER突变、TAM的激动作用、卵巢类固醇生成、TAM代谢改变以及抗雌激素结合位点表达水平升高。停用TAM和二线内分泌治疗可能对仍保留雌激素依赖性的他莫昔芬耐药乳腺癌有效。否则，对于已失去ER且对其他内分泌治疗无反应的雌激素非依赖性乳腺癌，应选择化疗。在此背景下，对于乳腺癌获得性抗雌激素耐药的管理，应考虑月经状态、雌二醇血清水平和类固醇受体状态。
