Longer HRT Use May Raise Breast Cancer Risk
Study Also Shows Higher Risk for Thinner Women Who Take Hormone Replacement Therapy
HRT and Breast Cancer Risk: Study Details continued...
That's bad news tempered with some not so bad, according to Saxena. "If you do get breast cancer from HRT, it tends to be the type more responsive to therapy."
Bottom line of the new analysis? "There are benefits in the relief of menopausal symptoms with hormone therapy, but the risks from hormone therapy are different for different women," Saxena says. "At the end of the day you want to be on hormone therapy for the least amount of time possible and at the lowest dose possible."
While Saxena can't pinpoint a number of years that are "safe," he says that he found elevated risks on combination therapy even for short-term use -- less than five years.
One co-author of the study, Christina A. Clarke, served as an expert witness for plaintiff lawyers pursuing litigation over Prempro hormone therapy.
The new analysis has findings that differ from other clinical trials, such as the Women's Health Initiative (WHI), says Rowan Chlebowski, MD, PhD, a medical oncologist at the LA Biomedical Research Institute in Torrance, Calif., and an investigator for WHI. But that's to be expected, he says, given the design of the two approaches.
The WHI, launched in 1991, included clinical trials and observational studies and tested hormone therapy and other interventions on the risks of heart disease, fractures, and breast and colorectal cancers.
For instance, in the WHI, long-term estrogen-only use, at least initially, reduced the risk of breast cancer, Chlebowski says.
But when it comes to practical decisions, the new analysis, Chlebowski tells WebMD, "probably doesn't change things too much."
For menopausal women, he says, the message is to take hormone therapy if needed to relieve menopausal symptoms for a time. "After a period of time, like a couple of years, reassess," he says.
According to the American Congress of Obstetricians and Gynecologists, a woman should take the smallest dose of hormone therapy that works for her, for the shortest possible time.
"This [finding] doesn't change the message," he says. And that is that the primary reason to take hormone therapy is for relief of menopausal symptoms, not long-term protection from disease.