Yesterday, The New England Journal of Medicine publishes a study which seems to show that the value of early detection may not affect breast cancer outcomes as much as previously thought. The study has been covered by The New York Times and just about every other media outlet you can think of, so I won’t belabor what others have already reported.
The upshot is this: Previous studies, done decades ago, show that early mammogram screenings could reduce breast cancer deaths by as much as 15 to 25 percent. This new study, which isn’t perfect, suggests that early detection may make far less of a difference, as little as 2 percent, maybe even 0 percent.
In the NEJM study, researchers follow women in Norway. The first group, aged 50 to 69, get early mammogram screenings and were treated by multidisciplinary “breast cancer teams” including surgeons, radiologists, oncologists, pathologists and nurses. In this group, breast cancer mortality decreases by 10 percent. The second group, aged 70 and older, do not get early mammogram screenings because they are not required at the time that this group was younger. This group did get the care of the multidisciplinary teams, however. The breast cancer mortality among the older women fell 8 percent. Subtract 8 from 10, and you get a mere 2 percent advantage among the women who got early mammograms.
Everyone, even the researchers, seems surprised by the results of this study. The researchers expected that mammograms would reduce mortality by 30 percent. That’s a lot more than the 2 percent difference they found. The New York Times story quotes a doctor from Sloan Kettering, where I got my second opinion, saying that this affirms that mammograms saves lives. A radiologist at UCSF, where I’m being treated now, tells The Times that the study shows her that if you get the same treatment and it doesn’t make a difference if you find the cancer early or later, then the early detection doesn’t matter. Hmm.
I don’t blame the docs for being conflicted. This flies in the face of everything I have been told since I turned 40, and especially since I was diagnosed with breast cancer. The mantra I hear again and again is, “Early detection makes all the difference.” Maybe this was more true before major medical centers created these breast cancer teams, before there were targeted hormone and protein drugs to treat breast cancer, before it was common to do surgery on breast cancer that couldn’t even be seen by the naked eye. And yet, it just makes intuitive sense that finding cancer early makes a difference. Isn’t it better if you treat a flu before it turns into pneumonia? Shouldn’t you bandage a bruised ankle bone before it becomes a broken one? Of course, intuition is not science.
As you read the stories about this study, you can sense how reluctant the doctors and the public health experts are to give up the “early detection” mantra. Reporters quote many experts saying that they would still get early mammograms if it was their breast, their risk of cancer.
Even before this study comes out, when my primary care doc in Brooklyn sits me down two months ago to tell me I have breast cancer, she also expresses regret at new standards that would not require women as young as 40 to get regular mammograms, but would push the mammogram requirement back to age 50.
“If you hadn’t already been on the mammogram track, we might not have found this cancer so early,” she tells me. “You’re the exception that disproves the rule. It makes me uncomfortable.”
I would not be writing this blog if my primary care doc had not sent me for my first mammogram at 40, if a radiologist in Manhattan had not been just a little paranoid, if she hadn’t made me come in for a followup image, if she hadn’t recommended a biopsy. It turns out I had a lot of cancer that had not yet spread, ductal carcinoma in situ, DCIS. But I had an invasive, though small, tumor in the middle of all that DCIS. Thought the complete pathology on that tumor is not back yet, the preliminary word is that it was a nasty, nasty little thing. All I can say is that I am so, so glad that my tumor does not get the chance to grow for three more years, until I turn 50. I doubt my posts would be so jokey in that case. I wonder if I would even be well enough to write them.
I know public policy and treatment need to be based on science. But I’m with the experts: Maybe in most cases, finding breast cancer early isn’t as important with all the improvements in breast cancer treatment over the last 20 years. But if it’s me, I’ll go for the early mammogram.