ABSTRACT
This chapter addresses the pharmacology of the different agents used in the adjuvant setting, the approach to drug selection, rationale for therapy duration, endocrine therapy toxicity and side effect management. The goal of adjuvant endocrine therapy is to disrupt the interaction between circulating hormones and the receptor in a targeted manner, reducing the risk of breast cancer relapse. Landmark adjuvant trials reported in the 1980s reported benefits in post-menopausal women taking tamoxifen at least as large as the benefits gained from ovarian ablation in the pre-menopausal group. A woman's menopause status critically determines choice of endocrine therapy agent. Menopausal status should be documented at the first surgical consultation for breast cancer. Tamoxifen is the agent of choice for most pre-menopausal women with oestrogen receptor positive breast cancer. Aromatase inhibitors are inactive in women with intact ovarian function and are contra-indicated as a single agent.
