Endocrine therapy of breast cancer

The aim of this literature study is to evaluate the various endocrine drugs used in the treatment of breast cancer in order to compare their therapeutic efficacy. Hormone-dependent metastasized breast cancer of post-menopausal women can be treated with four equivalent drugs: tamoxifen, megestrol, medroxyprogesterone, and--combined with steroid suppletion therapy--aminoglutethimide. Each of these drugs induces (partial) remissions in 50-60% of estrogen receptor-positive tumors. Because of its relatively few and less serious side-effects tamoxifen is the agent of first choice for soft tissue and lung metastases. Due to its potentially enhanced objective and more pronounced subjective side-effects, aminoglutethimide may be preferred in bone metastases. In view of the only minor activity of hormonal agents in liver metastases, combination chemotherapy with concomitant, sequential or alternating use of hormonal agents should be considered in this condition. Until now, only tamoxifen seems suitable for the treatment of premenopausal metastasized hormone-dependent breast cancer. In the adjuvant setting, preoperatively initiated and as soon as possible postoperatively continued endocrine therapy seems to be of the utmost importance to counteract (occult) metastases while reducing the need for extensive surgery.