They just won’t quit, will they?
Here’s an article in the New York Times which exemplifies so much of what is wrong with the debate regarding breast screening in particular and cancer screening in general.
The article introduces us to one Dr. Marisa Weiss, a radiation oncologist who is writing her third book for a popular audience on breast cancer, and who has founded a popular website, breastcancer.org, to urge women to, in her words, “Get that mammogram.”
Dr. Weiss herself been having annual mammograms for more than a decade when, at the age of 51, a mammogram revealed the presence of an “invasive” breast tumor. She has surgery (the tumor had not spread, so both radiation and chemotherapy were deemed unnecessary) and lived to tell the tale.
I don’t doubt any of this. I also don’t doubt that sometimes it rains after people do a rain dance. So what?
There is no convincing evidence that screening mammography saves lives. A meta-analysis by the respected Cochrane Collaboration showed that for every two thousand women who underwent regular screening mammography between the ages of 50 and 69, ten women would be unnecessarily diagnosed with (and, in some cases, treated for) breast cancer, while one fewer women would die from breast cancer. Now, if you think such a tiny reduction in risk can even be measured reliably, well, bully for you, but the only statistic that matters to you as an individual is the OVERALL death rate. We all die of something, be it breast cancer or a heart attack or a stroke or getting run over by a bus on your way to the mammography clinic. And the same meta-analysis showed that women who get screening mammography and those who do not have EXACTLY THE SAME DEATH RATE.
A Norwegian study published last September in the New England Journal of Medicine which controlled for advances in breast cancer treatment found that screening mammography was correlated with an even lower reduction in the risk of dying of breast cancer – on the order of one in two thousand five hundred, which was found not to be statistically significant.
The Norwegian study did not look at all-cause mortality, which is the only statistic that matters. If you don’t believe that, then you must believe that women who die from their breast cancer treatment are success stories, because, well, they didn’t die of breast cancer. Does anybody out there want to defend that? Do these women’s deaths not matter, just as long as the medical profession gets its cut?
By the way, that same study shows that the incidence of “invasive” breast cancer almost doubled in the decade after screening mammography was made routine in Norway – and it wasn’t even introduced into all of Norway’s counties at once. Unless you believe that some mysterious force caused the incidence of invasive breast cancer to spike at the exact same time mammography was made routine, you must believe that even a lot of cases of “invasive” breast cancer must regress on their own – or at least grow so slowly that they never bother the women until she dies of something unrelated. I wonder how many of these women who were unnecessarily diagnosed with “invasive” breast cancer were subjected to the tender mercies of the cancer treatment industry – and of these, how many of them now firmly believe that “a mammogram saved my life” and take it as a terrible personal insult whenever somebody suggests otherwise?
The author of the NYT piece apparently never though to ask how much of Dr. Weiss’s salary is paid by the manufacturers of the X-ray machines used in screening mammography, but never mind that for now. A more important point is this: mammography has been around for more than fifty years. Why are they still giving us anecdotes like the one in this article? Where are the DATA that shows that screening mammography reduces a woman’s chances of dying prematurely? I’m not talking about data that shows that is may give a woman a one in a thousand or one in two thousand less chance of having breast cancer, as opposed to something else, listed on her death certificate as the cause of her death. Where are the data that shows it delays the DATE of death?
And, in fairness, the author never claims otherwise. But she seems to be trying leave the uninformed reader with the impression that it does:
”While one cancer death is prevented for every 1,339 women in their 50s and every 377 women in their 60s who undergo screening, 1,904 women in their 40s would need to be screened for 10 years to prevent a single cancer death.”
One cancer death is prevented. That doesn’t mean anybody is living a day longer.
This isn’t about enabling women to make informed choices, much less is it about “saving lives.” It’s about getting women to submit to screening. This isn’t journalism – this is publicity.
Photo via Wikimedia Commons