But if there are other explanations for this story, we may let our complacency drift into a much more serious situation a couple of years down the road, resulting in an increase in the diagnosis of breast cancer, coupled with later stage diagnosis, which in turn means a poorer outcome.
Here are my concerns:
We were already seeing a slight decrease in the number of breast cancers year to year before the study. This could be due to lifestyle changes or some other unknown factor, but when you consider that this country doesn't appear to be getting healthier, that raises the concern that there may have been some other explanation for the decrease. Examples could be fewer mammograms in general and in particular for the increasing number of uninsured or under-insured women, or perhaps because of decreased access to mammogram facilities.
The next consideration is that the paper in JAMA was published in July of 2002. The authors of the current abstract report that there was a 6 percent decline in the incidence of breast cancer, especially in post-menopausal women, in the first half of 2003.
I have been a doctor and around medicine a long time. I have never seen a circumstance where a journal publishes an article and there is an immediate adherence to the recommendation and an immediate effect six months later. That simply doesn't happen.
The more likely scenario is that the article is read and publicized, it is reviewed by practicing physicians and their patients, and over time there is a gradual decrease in the use of the "offending" medication resulting in a benefit some years down the road.
Based on my personal observations (my wife is a gynecologist, and as a result I have attended several of their meetings and listened to a lot of talks on this issue), gynecologists by and large did withdraw many of their patients from combined HRT over time, but certainly they did not call their patients on the phone to say, "Stop your hormones immediately."
Then there is the biology of the disease itself.
It takes many, many years for a breast cancer to develop and become identified on a mammogram, and years more for it to become palpable in the breast in most circumstances.
Even if every woman stopped taking their hormone pills on July 18, there would still be many breast cancers that were already present in some stage of development.
I don't think those cancers disappeared in the next six or twelve months. That simply defies rational thought.
What I suspect may have happened is that withdrawal of hormone therapy in some way affected the growth of those cancers, but they didn't go away.
We do know that changes in the hormonal milieu can affect breast cancer progression.
Years ago, we used to do oophorectomies in young women with breast cancer and saw dramatic results.
We also used to use estrogen to treat breast cancer, again with remarkable results.
We would even see improvements in some women with breast cancer who had been taking estrogens for the treatment of their breast cancer, when their disease progressed and we stopped their estrogens. Some of these women actually had regression of their disease when estrogens were withdrawn.
One of my professors at the University of Pennsylvania commented regularly that changing the hormonal environment -- whether by addition or subtraction -- was key to understanding the treatment of breast cancer.