There’s a report in the New York Times today regarding a new international medical research study that indicates that some women with breast cancer can avoid chemotherapy.
“We can spare thousands and thousands of women from getting toxic treatment that really wouldn’t benefit them,” said Dr. Ingrid A. Mayer, from Vanderbilt University Medical Center, an author of the study. “This is very powerful. It really changes the standard of care.”(1)
Because of it’s importance, the paper made this article available to non-subscribers.
The study reports that gene tests on tumor samples can differentiate women who need chemo from those who do not. Those not receiving chemo would instead receive endocrine therapy — that is a drug that blocks the hormone, estrogen, or stops the body form making it.
What’s interesting is that endocrine therapy has been a standard follow-on treatment for women receiving chemo for breast cancer for more than 10 years. The most commonly used drug in this class is tamoxifen — a drug probably well known to every person with experience with breast cancer.
What the news report doesn’t address is the issue with tamoxifen — that is, that it can only be taken for five years before the effects of the drug start to reverse. Tamoxifen is a preventive for cancer in the first five years of use, but can actually encourage cancer growth if taken for a longer period. Tamoxifen also has side effects that may preclude some women from using it, or wanting to use it.(2) Whether those effects change in the absence of chemotherapy isn’t clear.
So, this is an exciting report, but it’s not a slam dunk. It is expected to result in changes to standard breast cancer therapy. You probably want to make sure your doctor knows about it. Being new, many won’t.