2012 EDUCATIONAL BOOK - American Society of Clinical Oncology

UPDATE OF THE OXFORD OVERVIEW
Fig. 2. Relevance of measured ER and
PR status to the effects of tamoxifen on the
10-year probably of recurrence.
Abbreviations: ER, estrogen receptor; PR,
progesterone receptor; RR, recurrence rate;
SE, standard error; (O-E)/V, (observedexpected)/variance.
Reprinted from The Lancet, 378, Early
Breast Cancer Trialists’ Collaborative
Group, Davies C, Godwin J, et al. Relevance
of breast cancer hormone receptors and
other factors to the efficacy of adjuvant
tamoxifen: Patient-level meta-analysis of
randomised trials, 771–784, 2011, with
permission from Elsevier.
22%. Contralateral breast cancer is reduced by approximately
40%. Tamoxifen for 5 years benefits all women with
ER-positive disease and benefits those with very high levels
of ER even more. To date, ER expression is the sole deter-
Fig. 3. Relationship of quantitative
levels of ER with benefits of tamoxifen.
Abbreviations: O-E, observed-expected;
ER, estrogen receptor; SE, standard
error.
Reprinted from The Lancet, 378, Early
Breast Cancer Trialists’ Collaborative
Group, Davies C, Godwin J, et al. Relevance
of breast cancer hormone receptors
and other factors to the efficacy of
adjuvant tamoxifen: Patient-level metaanalysis
of randomised trials, 771–784,
2011, with permission from Elsevier.
minant of likely benefit from tamoxifen. Endometrial cancer,
however, is increased by 2.3-fold following 5 years of tamoxifen.
The rate of endometrial cancer increases as much as
4-fold with 10 years of tamoxifen.
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