Q: My mother is taking Premarin but is having serious concerns regarding the risk of breast cancer. She’s considering stopping her medication. There is no history of breast cancer in our family, but she is plagued with fibrocystic breast disease. She’s worried that her fibrous cysts will make it difficult to identify a cancerous tumor should one appear. What are your thoughts on fibrocystic breast disease, hormone replacement therapy (HRT) and breast cancer? My mother is enjoying the benefits of HRT (no migraines, hot flashes, mood swings), but we are both concerned about the negative effects of estrogen.
A: The questions you are asking are among the most common I answer every day. The data on estrogen and breast cancer is very confusing. There are about a dozen studies in the medical literature that show that if you use estrogen replacement for more than 10 years post-menopause, you slightly increase your risk of developing breast cancer. However, there are about 40 other studies in the literature looking at that same question and showing no increased risk of breast cancer.
However, I think that estrogen does promote fibrocystic changes, and does produce breast pain in some women — even though I don’t think it causes cancer. Certainly the same measures that work for pre-menopausal women help post-menopausal women with breast pain. Cutting caffeine, and taking a “vitamin cocktail” — 100 mg of vitamin B6, 400 units of vitamin E, and two capsules per day of evening primrose oil — help most of my patients with breast cysts.
And of course, I would encourage your mother to have yearly mammograms, and do monthly self-examinations. However, if she feels well with the estrogen, and particularly if she is at risk for cardiac disease, osteoporosis, and even colon cancer or Alzheimer’s disease, I see no reason that she should stop her estrogen replacement therapy.