Breast cancer, menopause, and long-term survivorship: critical issues for the 21st century.

Breast cancer accounts for 33% of all incident cancers in women in North America, and there are an estimated >2 million breast cancer survivors in the United States today. Ovarian hormones are intimately involved in the initiation and promotion of breast cancer development, with targeted endocrine therapies being the most widely used as anticancer treatment. It is not surprising that these treatments frequently cause persistent menopausal symptoms in breast cancer survivors. In addition, adjuvant chemotherapy often induces premature menopause in younger patients with breast cancer. Some women at high risk for the development of breast cancer (e.g., precancerous breast disease, carriers of deleterious hereditary predisposition genes) experience vasomotor symptoms as a result of tamoxifen therapy or preventive oophorectomy. Clinical management of menopausal symptoms in these settings is complicated by the relative prohibition of hormonal therapies and the fact that breast cancer-directed therapies often exacerbate these menopausal symptoms. Thus, this special population of women requires unique management strategies and deserves separate consideration.