Estrogen replacement therapy for breast cancer patients.

Female reproductive hormones cause breast cancer. Long-term use of postmenopausal hormones increases the risk of breast cancer. The apparent survival advantage seen in women diagnosed with breast cancer while taking postmenopausal hormones may be due to the hormone-responsive nature of their tumors, diagnosis at an earlier stage, or other biases. Thus, the data indicating a survival advantage do not specify what the policies were on the use of hormones after diagnosis. Substantial evidence from studies of obesity confirms the association of higher estrogen levels with poorer prognosis. Tamoxifen (Nolvadex), acting as an antiestrogen in breast tissue, increases the likelihood of survival, as does oophorectomy in premenopausal women. Given these data, women diagnosed with breast cancer should use hormones sparingly. Alternatives to hormone therapy should be used for long-term prevention of heart disease and osteoporosis.