Jan. 28, 2011 -- A new study shows that having symptoms such as hot flashes during menopause appears to be tied to a lower risk of the most common kinds of breast cancer.
“There’s good news about hot flashes,” says Susan Love, MD, a breast cancer expert and author of Dr. Susan Love’s Menopause and Hormone Book.
Researchers from the Fred Hutchinson Cancer Center in Seattle interviewed more than 1,000 women with one of three kinds of breast cancer and compared them to nearly 500 randomly selected women of similar ages with no history of breast cancer.
“This is the first study to ever look at this association,” says study researcher Christopher I. Li, MD, PhD, a breast cancer epidemiologist in the Hutchinson Center’s Public Health Sciences Division.
Li stresses, however, that his study was not designed to show cause and effect, and that the connection between menopausal symptoms and breast cancer is still largely a mystery.
“We don’t know a whole lot about all the biology that’s at work here,” he says.
In particular, scientists don’t know what causes hot flashes, only that they appear to be linked to lower levels of the hormone estrogen.
Breast cancer, in turn, has been linked to higher levels of estrogen, so it may be that hot flashes are acting as a marker for the intensity of hormonal changes in the body, Li says.
Indeed, a previous study showed that women who experienced hot flashes several times a day had 35% to 45% lower estrogen levels compared with women who did not experience hot flashes or who only experienced them infrequently.