Abstract
Tamoxifen has been the standard of care for adjuvant endocrine therapy of early breast
cancer. In postmenopausal women, data now suggest that alternative agents (aromatase
inhibitors [AIs]) may have improved long-term risk:benefit profiles and thus have
the potential to improve outcome. The ‘Arimidex’, Tamoxifen, alone or in combination
(ATAC) trial has shown that anastrozole provides improved disease-free survival (DFS)
and time to recurrence, significantly reduced time to distant metastases and superior
overall tolerability compared with tamoxifen when used as initial adjuvant therapy.
Results have already led to a reconsideration of current recommendations for adjuvant
therapy. Other ongoing trials include studies that are evaluating the benefits of
sequencing of endocrine agents both within the standard 5-year adjuvant treatment
period and as additional therapy in the post-adjuvant period. Three recently reported
trials have suggested that switching from tamoxifen to an AI after 2–3 years of treatment leads to better outcomes than 5 years of tamoxifen. Finally, the
NCIC MA 17 trial has shown that switching to an AI after 5 years of tamoxifen improves
DFS compared with placebo.
These are momentous discoveries that have improved our biological understanding and
will inevitably change the management of breast cancer in the near future.
Keywords
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Article info
Publication history
Accepted:
May 18,
2005
Received in revised form:
May 4,
2005
Received:
March 10,
2004
Identification
Copyright
© 2005 Elsevier Ltd. Published by Elsevier Inc. All rights reserved.
