Endocrine Therapy for Breast Cancer Risk Reduction

Publication Date: September 3, 2019
Last Updated: March 14, 2022



  • Should be discussed as an option to reduce the risk of invasive BC, specifically ER-positive BC, in premenopausal women who are >35 years of age with a 5-year projected absolute BC risk >1.66% or with LCIS. Risk reduction benefit continues for at least 10 years.
  • Is not recommended for use in women with a history of deep vein thrombosis, pulmonary embolus, stroke, transient ischemic attack, or during prolonged immobilization.
  • Is not recommended for women who are pregnant, women who may become pregnant, or nursing mothers.
  • Is not recommended in combination with hormone therapy.
  • Follow-up should include a timely workup of abnormal vaginal bleeding.
  • Discussions with patients and health care providers should include both the risks and benefits of tamoxifen in the preventive setting.
  • Dosage: 20 mg/day orally for 5 years.
(EB, S)



Use of Endocrine Therapy for Breast Cancer Risk Reduction

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