Initial treatment of breast cancer with chemotherapy or hormone therapy can help prevent metastatic or recurrent breast cancer. For women with estrogen receptor-positive (ER+) Breast Cancer, treatment with tamoxifen or an aromatase inhibitor, or both, can also help prevent recurrence. Recent studies have shown that an aromatase inhibitor, such as exemestane (Aromasin), works even better than tamoxifen in postmenopausal women who are also ER+.^{7, 8} For more information, see the topic Breast Cancer.