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Review
. 2007 Dec;61(12):2051-63.
doi: 10.1111/j.1742-1241.2007.01587.x. Epub 2007 Sep 24.

The what, why and how of aromatase inhibitors: hormonal agents for treatment and prevention of breast cancer

C J Fabian  1
Affiliations
Review

The what, why and how of aromatase inhibitors: hormonal agents for treatment and prevention of breast cancer

C J Fabian. Int J Clin Pract. 2007 Dec.

Abstract

The third-generation aromatase inhibitors (AIs) anastrozole, exemestane and letrozole have largely replaced tamoxifen as the preferred treatment for hormone receptor - positive breast cancer in postmenopausal women. Approximately 185,000 new cases of invasive breast cancer are diagnosed yearly, and at least half of these women are both postmenopausal and eligible for adjuvant therapy with AIs. In addition, AIs are currently being tested as primary prevention therapy in large randomised trials involving tens of thousands of women at increased risk for breast cancer. Given the volume of use, internists will increasingly see postmenopausal women who are taking or considering treatment with AIs. Physicians need to be able to: (i) briefly discuss the pros and cons of using a selective estrogen receptor modulator such as tamoxifen or raloxifene vs. an AI for risk reduction and (ii) recognise and manage AI-associated adverse events. The primary purpose of this review is to help internists with these two tasks.

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Figures

Figure 1
Figure 1
Schematic of metabolic pathways in an ER-positive cell that can be affected by AIs. The left side represents the active pathways and cellular responses under normal estrogen control. The right side depicts the blockade of pathways involving ERs and the resultant cellular responses. AI, aromatase inhibitor; E2, estradiol; ER, estrogen receptor; MAP, mitogen-activated protein; PI-3, phosphoinositide-3; RTK, receptor tyrosine kinase; SERD, selective estrogen receptor down-regulator; SERM, selective estrogen receptor modulator
Figure 2
Figure 2
Schematic of organs with substantial aromatase activity
Figure 3
Figure 3
Metabolic pathways differentially targeted by aromatase inhibitors (AIs)
See this image and copyright information in PMC

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