A woman's heart

The impact of adjuvant endocrine therapy on cardiovascular health


  • Michael S. Ewer MD, MPH, JD,

    Corresponding author
    1. Department of Cardiology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas
    • Department of Cardiology, Unit 43, The University of Texas M. D. Anderson Cancer Center; 1515 Holcombe Boulevard; Houston, TX 77030===

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  • Stefan Glück MD, PhD

    1. Division of Hematology/Oncology, Department of Medicine, Miller School of Medicine, University of Miami, Miami, Florida
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Adjuvant therapy in postmenopausal women with breast cancer may contribute to the expression of underlying cardiovascular disease or expose the heart to additional toxicities. Tamoxifen remains an important component of endocrine therapy for breast cancer, although major clinical trials of the aromatase inhibitors (AIs) anastrozole, letrozole, and exemestane suggest that these agents are more effective and better tolerated alternatives to tamoxifen. The AIs inhibit the conversion of androgens to estrogen in postmenopausal women; consequently, their mechanism of action differs from that of tamoxifen. Accordingly, although it has been observed that tamoxifen has some favorable effects on cardiovascular risk, such as reducing total cholesterol levels, because of its partial estrogen-agonist properties, no such effects exist for the AIs. Some studies, particularly those that compare the AIs with tamoxifen, have suggested a less favorable impact of adjuvant AI therapy on cardiovascular risk. Comorbid conditions, including cardiovascular disease, emerge as competing causes of death as women with breast cancer continue to live longer, and the potential impact of adjuvant therapies on cardiovascular risk becomes an increasingly important consideration for clinicians. Cancer 2009. © 2009 American Cancer Society.