The news about hormone replacement therapy (HRT) that combines estrogen AND progestin is not good. In a newly released analysis of the ongoing Women’s Health Initiative (WHI) study, the combined hormone therapy has an increased risk of breast cancer and not many benefits. This does NOT include HRT that has only estrogen in it, which can only be used by women who do not have a uterus. (Estrogen alone can increase endometrial cancer, located in the uterus.)
The WHI study is a massive, long-term study undertaken by the National Institutes of Health (NIH) to clarify the health benefits and risks of HRT. This large clinical trial attempts to examine the long-term effect of estrogen plus progestin on the prevention of heart disease and hip fractures and measuring possible increases in breast and colon cancers.
In July 2002 the women in the WHI study who were taking the estrogen/progestin combination were told to stop. The Monitoring Board detected an increase in breast cancer in that group after taking the combination for an average of 5.2 years (not before) and no decrease in heart attacks, strokes, and blood clots. The Board determined that the risks outweighed the benefits and it would create greater harm to continue that portion of the WHI study.
In the intervening years, several other studies were published that suggested the cancers that were linked to the estrogen/progestin therapy were less deadly. Some studies also suggested some benefits.
A new analysis of the WHI study that now has 11 years of data, finds that the breast cancers in HRT treated women are just as deadly as the breast cancers that non-treated women got. And since the estrogen/progestin combination results in more episodes of breast cancer, more women who take the hormone combination will die of breast cancer than those who do not — simply because more will get cancer.
Dr. Patricia Ganz, director of cancer prevention and control research at UCLA’s Johnsson Comprehensive Cancer Center, was quoted in an LATimes article, “If you’re going to take these therapies, you need to know there’s an increased risk,”…”Make sure there’s a good indication. And don’t take them for a long period of time.”