Estrogen replacement therapy in patients with early breast cancer

Most physicians believe that estrogen replacement therapy is contraindicated once a patient is diagnosed with breast cancer. Recently, several studies have shown that estrogen replacement therapy may be safely used in patients with early breast cancer that has been treated successfully. These women can have severe menopausal symptoms and are at risk for osteoporosis. We reviewed the current status of women in our practice with breast cancer who received estrogen replacement therapy, who did not receive hormone replacement therapy, and who did not receive estrogenic hormone replacement therapy.

The study group consisted of 123 women (mean age, 65.4 +/- 8.85 years) who were diagnosed with breast cancer in our practice, including 69 patients who received estrogen replacement therapy for < or = 32 years after diagnosis. The comparative groups were 22 women who used nonestrogenic hormones for < or = 18 years and 32 women who used no hormones for < or = 12 years. The group who did not receive estrogenic hormone replacement therapy received androgens with or without progestogens (such as megestrol acetate). Of the 63 living hormone users, 56 women are still being treated in our clinic, as are 15 of the 22 subjects who receive nonestrogenic hormone replacement therapy. Follow-up was done through the tumor registry at University Hospital; those patients whose tumor records were not current were contacted by telephone.

There were 18 deaths in the 123 patients: 6 patients who received estrogen replacement therapy (8.69%), 2 patients who received nonestrogenic hormone replacement therapy (9.09%), and 10 patients who received no hormone replacement therapy (31.25%). Of the 18 deaths, 9 deaths were from breast cancer (mortality rate, 7.3%); 3 deaths were from lung cancer; 1 death was from endometrial cancer; 1 death was from myocardial infarction; 1 death was from renal failure; and 3 deaths were from cerebrovascular accidents. The 9 deaths from breast cancer included one patient who received nonestrogenic hormone replacement therapy (mortality rate, 4.5%), 6 patients who received no hormone replacement therapy (mortality rate, 11.3%), and 2 patients who received estrogen replacement therapy (mortality rate, 4.28%). The 9 non-breast cancer deaths included 4 patients who received estrogen replacement therapy (endometrial cancer [1 death], lung cancer [1 death], cerebrovascular accident [1 death], and renal failure [1 death]), 1 patient who did not receive estrogenic hormone replacement therapy group (myocardial infarction), and 4 patients who used no hormones (lung cancer, 2 deaths; stroke, 2 deaths). Carcinoma developed in one patient in the estrogen replacement therapy group in the contralateral breast after 4 years of hormone replacement therapy; she is living and well 2.5 years later with no evidence of disease. Metastatic breast cancer developed in one patient after 8 years of hormone replacement therapy; she is living with disease.

Estrogen replacement therapy apparently does not increase either the risk of recurrence or of death in patients with early breast cancer. These patients may be offered estrogen replacement therapy after a full explanation of the benefits, risks, and controversies.