After covering the pros and cons of hormone replacement therapy for the past several years, I was startled to see the just announced finding on hormones and breast cancer risks. Yeah, I knew hormones were associated with an increased risk of breast cancer, but now we hear that the dangers kick in after just three years. And the risk of getting a certain type of cancer is increased 400 percent! After hearing that bit of news, I wouldn't be surprised if all the women who haven't already torn up their HRT prescriptions—about 75 percent fewer women take hormones today compared with five years ago—do now.
But wait. The reality isn't quite as dire as it sounds. While hormones do raise the risk of a type of breast cancer called lobular carcinoma (which accounts for 20 percent of all breast cancers), they don't appear to increase the other kinds. What's more, if you look at the actual numbers, the increase in risk is still pretty small. The average 50-year-old white woman has a 1.3 percent chance of developing breast cancer in the next five years. With lobular accounting for only 1 in 5 breast cancers, a fourfold growth in its risk would raise her breast cancer chances to about 2 percent. And the heightened risk disappears within two to five years after women go off the hormones, says study author Christopher Li, an epidemiologist at the Fred Hutchinson Cancer Research Center in Seattle.
And if you're taking estrogen alone (without progesterone) to combat menopausal hot flashes and mood swings, you don't have to worry about any increased breast cancer risk, according to the study. "We think progesterone works hand in hand with estrogen in fueling cancer cell growth," Li tells me. Unfortunately, only women who have had hysterectomies can take estrogen on its own, because it poses a higher risk of uterine cancer.
Deciding whether or not to take HRT can make a woman feel like she's walking a tightrope. But this new finding doesn't really change the current wisdom much. If you can manage your menopausal symptoms on your own, skip HRT altogether. If not, women should take hormones for only as long as they need them, aiming for the lowest effective dose for the shortest amount of time.