Of great interest are the single nucleotide polymorphisms (SNIPs) that individually have minor effects of risk but are common. Some women will have several of these SNIPs to have an impact on their breast cancer risk, especially in combination with mammographic density and other known factors. An assessment of how SNIPs might improve risk assessment among high-risk women is needed for better targeting of preventive therapy. In a recent study, Cuzick et al evaluated a panel of 15 SNIPs and found that they are useful for refining risk estimates in women at high risk of developing breast cancer.52

In conclusion, there are many options for the prevention of ER-positive breast cancer, specifically in postmenopausal women who can be given a SERM or an AI. For premeno­pausal women, only tamoxifen can be potentially used as a preventive agent as AIs are not indicated in this group of women. It remains unclear how to prevent the incidence of ER-negative breast cancer, which occurs mostly in premeno­pausal women, and more research is needed to specifically target this unsolved matter.

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The author reports no conflicts of interest in this work.

Ivana Sestak, Centre for Cancer Prevention, Wolfson Institute of Preventive Medicine, Queen Mary University of London, Charterhouse Square, London, UK. 


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