If you are considering or currently using hormone therapy (HT) to ease menopausal symptoms such as hot flashes and night sweats, you’re probably keenly aware of the concerns about a link between HT and breast cancer. So I want to share new study results that help identify which HT users are and are not at increased risk for this dreaded disease. The surprising clue: Sore breasts.
Background: There are two basic types of menopausal HT—estrogen alone…and a combination of estrogen plus progestin (a synthetic progesterone-like hormone). A woman who has had a hysterectomy can take estrogen alone. For a woman with an intact uterus, the combination form of HT is given because the progestin protects against uterine cancer. A common side effect of both types of HT is breast tenderness.
Researchers examined the medical records of more than 27,000 postmenopausal participants in a study called the Women’s Health Initiative. The women took either estrogen-only HT, combination HT or a placebo for about five to seven years, on average, then were followed up for several more years. They received annual mammograms and breast exams and periodically answered questions about their health and symptoms, including breast tenderness.
Findings: Women whose breasts became tender within a year after starting combination HT were 33% more likely to get invasive breast cancer during the study period than combination HT users who did not develop new breast tenderness. Among women who were already prone to breast tenderness before the start of the study, use of combination HT doubled the risk for breast cancer. However, for women taking estrogen-only HT, no link was found between breast soreness and cancer risk—in fact, women in the estrogen-only group were less likely to develop breast cancer than women in the placebo group. Explanation: Combination HT use appears to increase breast density (the proportion of glandular or connective tissue to fatty tissue)—and dense breasts are a known risk factor for breast cancer.
Self-defense for women who are using or thinking about starting HT: Alert your doctor to any breast tenderness you may experience and include this factor in your discussion about the risks and benefits of HT…and be extra-sure to get regular mammograms and breast exams.