and Women's Center, Inc.
Suites 204 & 205
Columbia, MD 21044-2979
NAMS Response to New WHI Breast Cancer Data
New report from the Women’s Health Initiative (WHI) regarding estrogen plus progestin hormone therapy and breast cancer published in this week’s JAMA on 10/20/10 (Chlebowski RT, et al)
This new publication from the WHI focuses on breast cancer incidence and mortality associated with using combined conjugated equine estrogens and medroxyprogesterone acetate (Prempro; CEE 0.625 mg/d plus MPA 2.5 mg/d), a mean intervention time of 5.6 years and followed a mean total of 11 years. The new information relates to breast cancer mortality: the primary finding is of 1 to 2 extra deaths from breast cancer per 10,000 women per year. Specifically, for every 10,000 women in the study who were randomized to placebo, there were 1.3 deaths from breast cancer per year. For every 10,000 women randomized to combined hormone therapy, there were 2.6 deaths from breast cancer per year. These results apply to combination estrogen plus progestin and not to estrogen alone. The WHI found no increase in breast cancer risk with estrogen alone (without a progestin) among women with hysterectomy over an average of 7 years of randomized treatment.
Clinicians can help women put the breast cancer risk into perspective by informing them that the increased risk of breast cancer using estrogen plus progestogen for 5 years is very similar to the increased risk of breast cancer associated with having menopause 5 years later. This increased risk of breast cancer occurs with a woman’s own internal, natural estrogen and progesterone.
The current Position Statement from The North American Menopause Society recommends using hormone therapy only when needed to treat moderate to severe symptoms of menopause. Consistent with that approach is the recommendation to use the lowest effective dose for the shortest amount of time. Each woman, in consultation with her healthcare provider, needs to prioritize her midlife health concerns and determine whether hormone therapy is an acceptable choice for her.