Not quite. It is a little more complicated than that.
First, let me be honest about this and tell you on which side I fall. I've had my doubts about the usefulness of mammograms for a long time, ever since I had a surgical intervention back in the 1980s, with the removal of an 8cm tumor from a breast - a tumor that resulted benign and the whole operation could easily have been skipped with a simple biopsy (but in those days in Italy, and with the conservative MD I had, a biopsy was not considered as reliable as total removal). What really annoyed me at the time was the obvious fact that the mammogram hadn't revealed anything more than what was already known via a simple palpation.
So why do it at all? Anyone who's gone through a mammography knows how unpleasant it is, a machine that squeezes you flat in order to supposedly "photograph" better what's under the skin. Machines have improved since early days and are no longer so invasively painful, but it is still a deeply unpleasant experience.
Now my doubts are confirmed. It is an unnecessary experience. What the Canadian study shows without a shadow of a doubt are two things:
1. early detection of "lumps" do not change ultimate results in terms of number of lives saved because many of those super tiny lumps that only a mammogram shows actually disappear of themselves or never evolve to a cancerous stage; hence the overdiagnosis and "false positives".
2. what has changed are recent improvements in medical cures (e.g. drugs like tamoxifen) that have improved the survival rate for women (and men) with breast cancer.
So should we abandon mammograms? As I said earlier, not quite. They are still a useful adjunct after a normal palpation exam by your doctor has shown a problematic lump. But don't expect wonders from it. Just a confirmation of your doctor's exam.
I honestly believe that mammography, once touted as a fantastic means to "catch" cancer at an early stage, thus improving chances of survival, has done its time and is ready to be shelved in historic medical libraries. Even if it never really did anything more than a simple palpation could do, it still served a historic role in drawing women's attention to the problem of breast cancer.
Mammography in process: Shown is a drawing of a female having a mammogram. A mammogram is a picture of the breast that is made by using low-dose x-rays. (Photo credit: Wikipedia)