Murray J, Young O E, Renshaw L, White S, Williams L, Evans D B, Thomas J St J, Dowsett M, Dixon J M
Edinburgh Breast Unit, Western General Hospital, Edinburgh EH4 2XU, UK.
Breast Cancer Res Treat. 2009 Apr;114(3):495-501. doi: 10.1007/s10549-008-0027-0. Epub 2008 Apr 26.
Changes in proliferation as measured by Ki67 occur within 14 days of starting treatment with an aromatase inhibitor and these changes have been shown to be predictors of long term outcome. This study aimed to compare changes in proliferation following 14 days of treatment with anastrozole and letrozole.
Two hundred and six women with 209 estrogen receptor (ER) positive operable breast cancers (three bilateral) were randomly allocated to receive either 14 days treatment with 2.5 mg of letrozole or 1 mg of anastrozole prior to surgery. Changes in expression of estrogen (ER) and progesterone receptors (PgR) as assessed by ALLRED scores and proliferation as assessed by Ki67 were analysed. The HER2 status of each tumour was also assessed using a combination of the Hercept test and FISH.
Both letrozole and anastrozole reduced ER expression (ALLRED score) by a mean of 0.32 (0.20-0.44), P<0.001 and PgR fell by a mean of 2.54 (2.20-2.89) P<0.0001. Letrozole reduced proliferation from a geometric mean of 6.37% to 0.81%, P<0.0001 and anastrozole reduced proliferation from 5.81% to 0.77%, P<0.0001. There was no differences between drugs in the fall in ER, PgR or proliferation. Both letrozole and anastrozole produced significant falls in proliferation in both HER2 positive and HER2 negative cancers, all P<0.001.
14 days of both letrozole and anastrozole reduces proliferation, ER and PgR expression. No significant difference between these two drugs was identified.
通过Ki67测量的增殖变化在开始使用芳香化酶抑制剂治疗的14天内就会出现，并且这些变化已被证明是长期预后的预测指标。本研究旨在比较阿那曲唑和来曲唑治疗14天后增殖的变化。
206名患有209例雌激素受体（ER）阳性可手术乳腺癌（3例双侧）的女性在手术前被随机分配接受2.5mg来曲唑或1mg阿那曲唑治疗14天。分析通过ALLRED评分评估的雌激素（ER）和孕激素受体（PgR）表达的变化以及通过Ki67评估的增殖变化。还使用Hercept检测和FISH组合评估每个肿瘤的HER2状态。
来曲唑和阿那曲唑均使ER表达（ALLRED评分）平均降低0.32（0.20 - 0.44），P<0.001，PgR平均降低2.54（2.20 - 2.89），P<0.0001。来曲唑使增殖从几何平均值6.37%降至0.81%，P<0.0001，阿那曲唑使增殖从5.81%降至0.77%，P<0.0001。两种药物在ER、PgR下降或增殖方面无差异。来曲唑和阿那曲唑在HER2阳性和HER2阴性癌症中均使增殖显著下降，所有P<0.001。
来曲唑和阿那曲唑治疗14天均可降低增殖、ER和PgR表达。未发现这两种药物之间有显著差异。
