• Hormone therapy is another form of systemic therapy. It is most often used as an adjuvant therapy to help reduce the risk of cancer recurrence.
• Tamoxifen is the anti estrogen drug that has been used most often. Estrogen promotes the growth of breast cancers those containing estrogen receptors (ER-positive cancers) and progesterone receptors (PR-positive cancers). Because of this, several approaches to blocking the effect of estrogen or lowering estrogen levels are used to treat ER-positive and PR-positive breast cancers.
• An aromatase inhibitor maybe recommended by private oncologist at some point during adjuvant therapy, for postmenopausal women whose cancers might respond to hormone therapy. Using this drug, after a course of tamoxifen, has been shown to better reduce the risk of cancer recurrence compared to using just tamoxifen alone for 5 years. But an aromatase therapy is costly.

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