Alas, two long-known protective factors — early childbearing (in the teens and 20s) and prolonged breastfeeding — run headlong into the life goals of many modern women who seek graduate degrees and professional advancement, as well as young women financially unable to support a family.
Many older women run into another confusing and controversial decision: whether and for how long to take hormone therapy to counter life-disrupting symptoms of menopause. Barring an earlier history of breast cancer, current advice for women who have not had a hysterectomy is to take combination hormone therapy (that is, estrogen and a progestin) for as short a time as needed to control symptoms but no longer than a few years.
A recent study, published July 28 in JAMA, described the long-term effects on breast cancer risk among 27,347 postmenopausal women randomly assigned to take hormone replacement or not. The authors, led by Dr. Rowan T. Chlebowski at UCLA Medical Center, reviewed the health status of the participating women more than two decades later.
Among the 10,739 women who had no uterus and could safely take estrogen alone (progestin is typically added to prevent uterine cancer), menopausal hormone therapy significantly reduced their risk of developing and dying from breast cancer. However, among the 16,608 women with a uterus who took the combination hormone therapy, breast cancer incidence was significantly higher, although there was no increased risk of death from the disease.
In commenting on these results, Dr. Christina A. Minami, a breast cancer surgeon at Brigham and Women’s Hospital, and Dr. Rachel A. Freedman, an oncologist at Dana-Farber Cancer Center, wrote that the new findings “are unlikely to lead to the use of hormone therapy for the sole purpose of breast cancer risk reduction.”
But Dr. Freedman said in an interview, “If I’m counseling a patient who’s really miserable with menopausal symptoms and is a candidate for estrogen only, these findings are reassuring that her breast cancer risk will not be any higher over time.”
Then there’s the possibility of taking a daily drug to suppress a potential breast cancer in high-risk women who have not yet had the disease. Dr. Jeffrey A. Tice, an internist at the University of California, San Francisco, suggested that women’s doctors use one of the several risk assessment calculators to determine how likely the patient might be to develop breast cancer within the next five or 10 years.