Historical perspective on hormonal therapy of advanced breast cancer

Background: Endocrine therapy is the preferred first-line therapy in patients with nonaggressive, receptor-positive, metastatic breast cancer. Endocrine therapies in these patients are as effective as chemotherapy in terms of survival and tumor response. In addition, hormonal therapies produce fewer and less severe adverse effects than does chemotherapy. Classes of endocrine therapy currently on the market include selective estrogen receptor modulators (SERMs), aromatase inhibitors, and progestins. For several decades, tamoxifen has been considered the gold standard of therapy. However, despite its proven efficacy, a high proportion of patients do not respond. Therefore, a need exists for alternative therapies or for agents to use following tamoxifen failure. Objective: This review article highlights the various endocrine options available for patients with advanced breast cancer and discusses new agents on the horizon. Conclusions: Although more studies are needed to determine the optimal sequence of hormonal therapy and the ideal agent within each class, the availability of new and multiple options is encouraging for women with advanced breast cancer.