The hormone replacement therapy study aimed to see if different types of treatment (estrogen alone or estrogen-plus-progestin), the form of treatment (pill, patch, cream), or whether or not it was taken sequentially or continuously affected ovarian cancer risk.
During the 1990s, hormone replacement therapy was widely used by women to help control menopausal symptoms. However, data from the Women's Health Initiative study in 2002 suggested that the treatment raised risks for cardiovascular events and breast cancer, and rates of use fell precipitously.
In the new study, the authors examined data on almost 127,000 postmenopausal women in 10 European countries.
"Current use of hormone therapy was associated with a small but significant increased risk of ovarian cancer [29 percent compared to women who had never used hormone therapy] but there was no association for former use," said study lead author Konstantinos Tsilidis, a postdoctoral fellow in the Cancer Epidemiology Unit at the University of Oxford.
The longer a woman used the therapy, the higher the risk, although the only significant risk was seen among women who used hormone therapy for over five years. There seemed to be no difference in risk between type of therapy, by regimen or route of administration.
A third study presented at the conference found a heavy burden of side effects -- including hot flashes, sleep aberrations, hair loss and leg cramps -- in women taking aromatase inhibitor medications to treat their breast cancer.
"Aromatase inhibitors are associated with the new onset of a number of symptoms that occur much more frequently in women with breast cancer compared to women of the same age without cancer," said study lead author Lisa Gallicchio, an epidemiologist with the Prevention and Research Center at Mercy Medical Center in Baltimore. "These symptoms may affect quality of life and
All rights reserved