Hormone replacement therapy in previously treated breast cancer patients.

We report our experience with 25 women previously treated for breast cancer who subsequently received hormone replacement therapy (HRT) for the relief of menopausal symptoms and the prevention of postmenopausal cardiovascular disease and osteoporosis. Two patients had in situ disease, 13 had stage I disease, 7 had stage II disease, 1 had stage III disease, and 2 had invasive cancer of undetermined stage. Seventeen patients (group I) began HRT less than 24 months after primary breast cancer therapy, and 8 patients (group II) began HRT more than 24 months after breast cancer therapy. The HRT-free interval for group I patients averaged 7.9 months and for group II patients averaged 64.5 months. The average period of observation while receiving HRT for the entire group was 35.2 months (range: 24 to 82 months). Three of 25 patients have had a recurrence, all in group I. One patient developed local recurrence after breast conservation treatment, and her condition was salvaged by further wide excision. Two patients developed recurrence after mastectomy, and one patient ultimately died of systemic disease. The overall survival rate for the entire group was 96%. Overall survival of high-risk group I patients, with a mean follow-up of 30.4 months, was 94%. We recognize that this report of HRT in a small group of patients does not have the power to demonstrate an adverse effect of HRT on breast cancer. However, the lack of an obvious adverse effect of HRT in this group of breast cancer patients and the known beneficial effect of HRT on postmenopausal cardiovascular disease and osteoporosis warrant formal prospective trials of HRT in such patients.