American Journal of Cancer

, Volume 2, Supplement 1, pp 7–11 | Cite as

Letrozole versus Tamoxifen as First-Line Treatment for Metastatic Breast Cancer

A Survival Analysis
Review Article


Third-generation aromatase inhibitors (AIs) have emerged as effective first-line treatment and after progression with tamoxifen for postmenopausal women with hormone receptor-positive metastatic breast cancer. In a recent multicenter, randomized, phase III trial of letrozole and tamoxifen, letrozole was significantly more effective than tamoxifen with respect to time to tumor progression (9.4 vs 6.0 months), objective response rate (32% vs 21%) and clinical benefit rate (50% vs 38%). Patients were more likely to remain on initial letrozole treatment and received significant survival benefits from 6 months to 2 years compared with those receiving tamoxifen. Letrozole is approved for first-line use and with improved efficacy over tamoxifen should be considered as a standard treatment option for patients with hormone-sensitive metastatic breast cancer. Additional studies comparing AIs as treatment for advanced disease are necessary to determine whether treatment advantages are class specific or relative to individual AIs.


Tamoxifen Metastatic Breast Cancer Letrozole Anastrozole Exemestane 
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The author has provided no information on sources of funding or on conflicts of interest directly relevant to the content of this review.


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Copyright information

© Adis International Limited 2003

Authors and Affiliations

  1. 1.Department of OncologyFinsen CenterCopenhagenDenmark

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