Patients who respond to endocrine therapy or who have periods of stable disease exceeding four to six months should be observed for possible withdrawal responses at the time of disease progression. Treatment Sequence for Postmenopausal Women A suggested sequence for the use of endocrine agents in postmenopausal women is shown in Fig 2. Tamoxifen should be the first-line agent of choice in this setting. For women receiving tamoxifen in the adjuvant setting who develop metastatic disease, tamoxifen should again be considered if the duration from completion of tamoxifen to the development of metastases is longer than one year. For second-line therapy, the aromatase inhibitors have moved ahead of megestrol acetate based on their slightly better efficacy and more favorable toxicity profile.
Aromatase inhibitors avoid the weight gain associated with progestins.
Glucocorticoids can also be considered for these patients. Since all therapy in patients with metastatic breast cancer is palliative, continuing endocrine therapy for as long as possible especially in patients with minimal or no symptoms and slowly progressive disease is a good strategy. Current status of endocrine therapy for metastatic breast cancer. A randomized trial in postmenopausal patients with advanced breast cancer comparing endocrine and cytotoxic therapy given sequentially or in combination. The Australian and New Zealand Breast Cancer Trials Group, Clinical Oncological Society of Australia.