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Postoperative Endocrine Therapy for Invasive Breast Cancer

  • Leisha A. Emens
  • Nancy E. Davidson
Chapter
Part of the Cancer Treatment and Research book series (CTAR, volume 151)

Estrogen plays a key role in mammary carcinogenesis, identifying the pathways that regulate estrogen function as major targets for breast cancer therapy. Expression of the estrogen receptor α (ERα) or the progesterone receptor (PR) is a widely recognized predictor of response to hormonal therapy [1]. Studies of endocrine manipulation conducted in advanced breast cancer have revealed response rates of 80% for ER+/PR+ tumors, 40–45% for ER–/PR+ tumors, 25–30% for ER+/PR– tumors, and less than 10% for ER–/PR– tumors. More recently, data have demonstrated that over-expression of ER or PR in at least 1% of breast tumor cells indicates potential responsiveness to endocrine therapy [2, 3]. In the absence of ER or PR expression, endocrine therapy is not indicated. These observations highlight the importance of an accurate measurement of ER and PR expression in the primary tumor in therapeutic decision-making. Currently, quality-controlled quantitative immunohistochemistry is the method of choice [4, 5].

Keywords

Breast Cancer Overall Survival Premenopausal Woman Aromatase Inhibitor Luteinizing Hormone Release Hormone 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Department of OncologyThe Johns Hopkins UniversityBaltimoreUSA
  2. 2.University of Pittsburgh Cancer Institute, University of Pittsburgh School of MedicinePittsburghUSA

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