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New study stirs up controversy (again) about breast cancer screening

REUTERS/Eric Gaillard
“While no one can dismiss the possibility that screening may help a tiny number of women, there’s no doubt that it leads many, many more to be treated for breast cancer unnecessarily.”

A study published last Wednesday in the New England Journal of Medicine (NEJM) provides more evidence that the benefits of regular mammogram screenings have been oversold to women.

It’s also reigniting the sometimes ugly controversy over such screening.

The study was conducted by Dr. Archie Blyer of St. Charles Health System in Oregon and Dr. H. Gilbert Welch of the Dartmouth Institute for Health Policy & Clinical Practice in New Hampshire. Welch, author of the book “Overdiagnosed: Making People Sick in the Pursuit of Health,” has long argued that too much of what is considered standard medical practice in the United States is either ineffective or, worse, harmful to our health.

For the NEJM study, Welch and Blyer used 32 years (1976 to 2008) of breast cancer data from the National Cancer Institute’s Surveillance, Epidemiology and End Results (SEER) program to determine the effectiveness of breast screening.

What they found was disappointing, to say the least, as Welch explained in an opinion piece he wrote last week for the New York Times:

After correcting for underlying trends and the use of hormone replacement therapy [which has been linked to an increased risk of breast cancer], we found that the introduction of screening has been associated with about 1.5 million additional women receiving a diagnosis of early stage breast cancer.

That would be a good thing if it meant that 1.5 million fewer women had gotten a diagnosis of late-stage breast cancer. Then we could say that screening had advanced the time of diagnosis and provided the opportunity of reduced mortality for 1.5 million women.

But instead, we found that there were only around 0.1 million fewer women with a diagnosis of late-stage breast cancer. This discrepancy means there was a lot of overdiagnosis: more than a million women who were told they had early stage cancer — most of whom underwent surgery, chemotherapy or radiation — for a “cancer” that was never going to make them sick. Although it’s impossible to know which women these are, that’s some pretty serious harm.

But even more damaging is what these data suggest about the benefit of screening. If it does not advance the time of diagnosis of late-stage cancer, it won’t reduce mortality. In fact, we found no change in the number of women with life-threatening metastatic breast cancer.

Still, Welch adds, breast-cancer data offer women some good news, too. “Breast cancer mortality has fallen substantially in the United States and Europe,” he writes. “But it’s not about screening. It’s about treatment. Our therapies for breast cancer are simply better than they were 30 years ago.”

ACS: ‘Women should be fully informed’

Dr. J. Leonard Lichtenfeld, the deputy chief medical officer for the American Cancer Society, also wrote an opinion article about the study last week. Calling Blyer and Welch “highly regarded researchers,” he explained that although the ACS was not going to be changing its breast cancer screening recommendations any time soon, it recognizes that the society’s views on the subject are not the only legitimate ones.

As of today,  we continue to recommend women at average risk for breast cancer should have a screening mammogram every year beginning at age 40, along with a clinical breast exam.

What frequently gets “lost in the sauce” is that we also acknowledge the concerns that have been raised regarding the matter of over diagnosis and the benefits, risks and harms of screening mammograms. These are important, and women should be fully informed as they make a decision about what is right for them.

Yes, we obviously believe screening should begin at age 40, but unlike some recent media reports suggest, we do realize that other respected experts do not agree with us.

‘First and foremost: Tell the truth’

Welch, however, argues that no matter how sincerely the medical community believed in annual mammograms and “the virtue of early diagnosis” in 1990, when widespread mammography screening was first implemented in the United States, it’s wrong to continue that policy.

“While no one can dismiss the possibility that screening may help a tiny number of women,” he writes, “there’s no doubt that it leads many, many more to be treated for breast cancer unnecessarily. Women have to decide for themselves about the benefit and harms.”

“First and foremost, tell the truth: women really do have a choice,” he adds.

You’ll find the NEJM study on the journal’s website. You can read the opinion pieces by Welch and Lichtenfeld at the New York Times and ACS websites, respectively.

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Comments (2)

  1. Submitted by Virginia Martin on 11/26/2012 - 02:44 pm.

    breast cancer screening

    I wish something more had been written about overtreatment. In the ’90s, I had a mastectomy, thinking it was my best option after learning I had cancer in my breast. I had two male doctors, an oncologist and a surgeon, who thought my decision was good. But the more I read, the more I realize I probably didn’t have to do anything. It was so tiny and in situ and at the very least I could have waited to find out if it needed treatment. One reason I decided on this was that I would not need any more treatment: I was “cured.” But from my reading, I think it was really “precancerous,” and nothing needed to be done.
    At the time it was hard to find alternative views. I read a couple of books; my regular doctor told me she would have made the same choice; there didn’t seem to be many other places to get more information. .

  2. Submitted by Donna Pinto on 11/27/2012 - 12:44 am.

    DCIS 411

    So grateful for this study and article! I was diagnosed with DCIS 3 years ago and from the get-go I felt that I was being over-diagnosed and over-treated. I had 1 needle biopsy and 3 lumpectomies and still Drs recommended me to have more surgery (and to consider removing my breast), 6 weeks of daily radiation or tamoxifen for 5 years — for low grade DCIS — which highly respected Breast surgeons/oncologists have said should be left alone with active surveillance. I have done a lot of homework, got 2nd, 3rd and 4th opinions and thankfully chose to take an “alternative” path — one that felt much more sane for my particular DCIS dilemma. I created a website/blog to share my on-going journey and offer support to others like me who are searching for better solutions to a very confusing & overwhelming diagnosis….largely due to mammograms. I hope more women become “fully informed” as this article says!!! Please visit my blog: Peace and good health to all, Donna

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