Dr. Leon Speroff recently stepped down as director for the Women's Health Research Unit at Oregon Health & Science University.
How does hormone replacement therapy affect breast cancer and heart disease?
Breast cancer remains the biggest fear in women and clinicians and we have multiple, multiple studies that have found a small, and I emphasize small increased risk of breast cancer associated with hormone therapy. Here is the problem. The problem is that we do not know the answer to this very important question. Do these studies indicate a small increased risk of breast cancer or do they reflect the effect of hormones, estrogen or estrogen plus progestin on tumors that are already there. There is a good reason to believe that they are reflecting an impact on tumors already there. The studies find this increased risk of breast cancer very fast within a year or two even and everybody knows on the average it takes 10 years for a breast cancer cell to become clinically detectable. It does not happen that fast. Secondly women who have breast cancer who are taking hormone therapy have better outcomes. They have tumors that are better differentiated, less aggressive, and they have better outcomes, so it is very possible that rather than harmful exposure especially to estrogen and progestin actually is beneficial causing an effect on a cancer that is already there that leads to its earlier detection when it has a better chance of being cured. So, there remains this image in the public as well as with clinicians that there are these risks of heart disease and breast cancer associated with hormone therapy, but in fact:
1. The risks were over estimated.
2. In the younger postmenopausal women there probably is no risk. In fact I am convinced there is no risk of heart disease; it actually protects and finally rather than actually increasing the risk of breast cancer, the hormone therapy may be producing a beneficial effect.
I think that is wonderful and isn’t that the news we are kind of looking for. We are looking for good news.