What are aromatase inhibitors?
Aromatase inhibitors reduce estrogen by blocking an enzyme called aromatase and keeping it from converting androgens into estrogen. Both pre-and postmenopausal women can use tamoxifen as hormonal therapy. But only postmenopausal women can use an aromatase inhibitor. That’s because the ovaries of postmenopausal women no longer produce significant amounts of estrogen so they get most of their estrogen from the conversion of androgens into estrogen by the aromatase enzyme, while premenopausal women get most of their estrogen directly from their ovaries Breast tumours can either be sensitive to estrogen (ER-positive), sensitive to progesterone (PR-positive), sensitive to both (ER-positive/PR-positive), or to neither (ER-negative /PR-negative). If a woman’s tumour is hormone-positive (ER-positive or PR-positive), some type of hormonal therapy may slow or stop the growth of the cancer. Until fairly recently, surgery was employed to reduce hormones in the system either removing the ovaries of
