Looking back the years, numerous studies have shown that hormone replacement therapy increases a woman’s risk of developing breast cancer. But to many women, questions about side effects, hormone combinations and length of hormone use are still unanswered, causing confusion. And some continue to take hormones to relieve menopausal symptoms because they don’t know where they fall in the HRT spectrum.
Attempting to clarify the risks versus the benefits, a report published in Cancer Epidemiology, Biomarkers and Prevention, and conducted by researchers at the University of Southern California, looked at data from a large trial group, called the California Teachers Study. Investigators were particularly interested in the more than 2,800 women in the study who were diagnosed with breast cancer.
When looking at hormone use, investigators found women who reported using just estrogen therapy for 15 years or more had a 19 percent greater risk of breast cancer compared with women who never used hormone therapy. And for women who used an estrogen and progestin combination or EPT for more than 15 years, their risk of developing breast cancer jumped to 83 percent.
“This is evidence that the story is complicated,” said Dr. Tanmai Saxena, an MD/PhD student at the Keck School of Medicine at the University of Southern California. “The benefits of hormone therapy for relief of postmenopausal symptoms among women are clear, but the risks are more complicated than we had previously thought.”
Risk also varied according to a woman’s BMI or body mass index with the greater risks for thinner women. That was surprising, because other studies have shown obesity to be linked to breast cancer. But when using hormones the statistics were different. Those with a BMI less than 30 appeared to have an increased risk of breast cancer with combined hormone therapy; while the risk was strongest among women with BMI less than 25. In contrast, obese women or those with a BMI of 30 or higher, had no further increase in risk associated with using combined hormone therapy.
Related posts:
Discussions