Current status of endocrine treatment of carcinoma of the breast

Sequential administration of endocrine therapies can result in objective remission in a significant fraction of patients with metastatic breast cancer. Combined hormonal therapies and combined hormonochemotherapies have not resulted in better results than the sequential administration of these same therapies. Tamoxifen (an antiestrogen) given as an initial therapy results in local control of the disease in a significant fraction of patients with locally advanced breast cancer who are not candidates for cytotoxic therapy. Tamoxifen as an adjuvant therapy for operable breast cancer prolongs disease-free survival and reduces mortality in patients greater than 50 yr of age with higher estrogen receptor concentrations. The role of tamoxifen as adjuvant therapy for patients less than 50 yr of age remains unclear. Also, adjuvant tamoxifen in combination with cytotoxic drugs has not produced superior results, and the duration of adjuvant tamoxifen therapy remains to be determined. Experimental data suggest prolonged administration of tamoxifen may be needed to control micrometastases.