Health News Review

There has been much reaction to a paper in the New England Journal of Medicine, “Effect of Three Decades of Screening Mammography on Breast-Cancer Incidence.” It is at times like this that a lone blogger like me on a holiday weekend can easily feel overwhelmed by the enormity of the task of trying to capture the discussion with accuracy, balance and completeness.  With that caveat, I make a humble and admittedly limited attempt.

First, interested readers should not miss the NEJM forum offering a poll and comments section after posing a case vignette of a 40-yar old woman and the mammography decision and this:

Which one of the following approaches do you find appropriate for women who, like the woman in the vignette, are at average risk? Base your choice on the published literature, your own experience, recent guidelines, and other sources of information, as appropriate.

  • Option 1: Recommend Screening Mammography Starting at the Age of 40
  • Option 2: Recommend Screening Mammography Starting at the Age of 50
  • Option 3: Do Not Recommend Screening Mammography

Dr. Gil Welch, one of the authors of the “Effect of Three Decades…” analysis, wrote a New York Times opinion piece, “Cancer Survivor or Victim of Overdiagnosis?” in which he summarized:

“So here is what we now know: the mortality benefit of mammography is much smaller, and the harm of overdiagnosis much larger, than has been previously recognized.

But to be honest, that general message has been around for more than a decade. Why isn’t it getting more traction?

The reason is that no other medical test has been as aggressively promoted as mammograms — efforts that have gone beyond persuasion to guilt and even coercion (“I can’t be your doctor if you don’t get one”). And proponents have used the most misleading screening statistic there is: survival rates. A recent Komen foundation campaign typifies the approach: “Early detection saves lives. The five-year survival rate for breast cancer when caught early is 98 percent. When it’s not? It decreases to 23 percent.”

Survival rates always go up with early diagnosis: people who get a diagnosis earlier in life will live longer with their diagnosis, even if it doesn’t change their time of death by one iota. And diagnosing cancer in people whose “cancer” was never destined to kill them will inflate survival rates — even if the number of deaths stays exactly the same. In short, tell everyone they have cancer, and survival will skyrocket.

Screening proponents have also encouraged the public to believe two things that are patently untrue. First, that every woman who has a cancer diagnosed by mammography has had her life saved (consider those “Mammograms save lives. I’m the proof” T-shirts for breast cancer survivors). The truth is, those survivors are much more likely to have been victims of overdiagnosis. Second, that a woman who died from breast cancer “could have been saved” had her cancer been detected early. The truth is, a few breast cancers are destined to kill no matter what we do.”

Dr. Len Lichtenfeld wrote on the American Cancer Society blog, “Breast Cancer Screening: The Search for Truth.” Excerpt:

We live in a headline driven world. The role of mammography for women is not immune to that influence. There will be many, many headlines on this topic, but too few folks will actually read the body of the article. And there is no telling how the body of any particular media article is going to portray the story, whether it be written to scare women or provide them with accurate information.

There is no way to tell how women are going to make up their minds to get screened or not get screened for breast cancer, but I can bet you there are going to be some who see the headlines and decide that mammography is not for them. Unfortunately, the researchers can’t tell them whether or not they made the right decision for themselves as an individual. We just don’t have the science to answer that question for any individual woman. So it comes down to basic facts: until science supplies us with the accurate answer, each woman has to make a decision regarding screening mammography. Hopefully that decision will be an informed one through discussion with a knowledgeable health professional in conjunction with reliable information available from other sources (such as the American Cancer Society at  www.cancer.org).

Many of us are concerned that women will read or hear the headline and forego screening mammograms altogether. We at the American Cancer Society – and I suspect many other experts-do not believe that would be the right approach. At least pick a suggested screening program that is right for you. We would recommend our guidelines, but we recognize there are others.

But at the end of the day, do not believe that the message delivered today is the end of the discussion. It is not. There was a different message delivered in other research papers last month, as there have in years past and will be in years to come until we get the scientific answers and guidance we need.

The search for the truth must continue unabated. Too many lives depend on it.

And then there are our readers.  One of them, Dr. Bradley Flansbaum, hospitalist and blogger at The Hospitalist Leader, sent us his comments:

The trial looked at the 30-year increase in early breast cancer diagnosis with the 1980′s introduction of mammograms, without a concurrent drop in late stage illness (overdiagnosis).  My criticism however, stems from the NPR/Kaiser Health News coverage the study received.

I am very bothered over this passage:

The ACR (American College of Radiology) statement’s main criticism is that Welch and Bleyer don’t account for what the radiologists say was a steady increase in the incidence of invasive breast cancer. They say that can explain why mammography didn’t lower the incidence of advanced breast cancer more.

Welch rejects that claim. “Why was breast cancer incidence so stable in the late ’70s, only to shoot up in the 1980s – the very time mammography was introduced?” he writes in an email. “Why didn’t incidence rise dramatically in women under 40 — those not exposed to screening?”

Welch is no newcomer to debates over the benefits and harms of diagnostic screening tests. In fact, he’s a well-known iconoclast, who last year published the popular book Overdiagnosed: Making People Sick in the Pursuit of Health.

“He has a preexisting bias, just as those of us in the breast imaging community have a preexisting bias,” Lee says. “The truth probably lies somewhere in between.”

Welch’s analysis was a large trial published in a peer reviewed journal. What evidence does Dr. Lee offer to counter the findings of Dr. Welch, other than an increase in “invasive breast cancer” and “bias”?  A false equivalence through my lens, and I see no references or push back from the journalist.  Dr. Lee’s contention may be true, but if you wish to rebut the conclusions of the work, bring or research your own.  More to the point, convey this to the reader.

She concludes with, “The truth probably lies somewhere in between.”  Not quite.

Addendum on November 25: Dr. Welch has posted an explanatory video on YouTube, “NEJM Screening Mammography – Understanding the Research.”

Addendum on November 28: The New York Times published a letter to the editor, “The Value of Mammograms,” from nine doctors and one nurse who wrote:

“We who battle breast cancer daily are horrified by H. Gilbert Welch’s repeated attacks on screening mammograms (“Cancer Survivor or Victim of Overdiagnosis?” Op-Ed, nytimes.com, Nov. 22). Would he have us return to the era when tumors were discovered only when they were large enough to be felt, meaning more disfiguring surgery, prolonged chemotherapy and lower cure rates?

His flawed reanalysis of old data lacks actual screening information, applies arbitrary adjustments for hormone use and makes an unjustified assumption that breast cancer incidence is not truly rising.

In contrast, prospective randomized trials of mammography have been reviewed and accepted globally: screened women have smaller, more curable cancers that are treatable with cosmetically superior surgery and less toxic medical therapy.

Early diagnosis and better treatment are partners. Would Dr. Gilbert, or any rational person, ignore a likely cancer on a mammogram and wait until it grows into a large mass while it possibly spreads throughout the body?”

But Dr. David Newman’s piece on the NYT website, “Ignoring the Science on Mammograms,” stated:

“It is affirming to see this newest study. But it raises an awkward question: why would a major medical journal publish an observational study about the effects of screening mammography years after randomized trials have answered the question? Perhaps it is because many doctors and patients continue to ignore the science on mammograms.

For years now, doctors like myself have known that screening mammography doesn’t save lives, or else saves so few that the harms far outweigh the benefits. Neither I nor my colleagues have a crystal ball, and we are not smarter than others who have looked at this issue. We simply read the results of the many mammography trials that have been conducted over the years. But the trial results were unpopular and did not fit with a broadly accepted ideology—early detection—which has, ironically, failed (ovarian, prostate cancer) as often as it has succeeded (cervical cancer, perhaps colon cancer).

More bluntly, the trial results threatened a mammogram economy, a marketplace sustained by invasive therapies to vanquish microscopic clumps of questionable threat, and by an endless parade of procedures and pictures to investigate the falsely positive results that more than half of women endure. And inexplicably, since the publication of these trial results challenging the value of screening mammograms, hundreds of millions of public dollars have been dedicated to ensuring mammogram access, and the test has become a war cry for cancer advocacy. Why? Because experience deludes: radiologists diagnose, surgeons cut, pathologists examine, oncologists treat, and women survive.

Medical authorities, physician and patient groups, and ‘experts’ everywhere ignore science, and instead repeat history. Wishful conviction over scientific rigor; delusion over truth; form over substance.”

————————————–

Follow us on Facebook,

and on Twitter:

https://twitter.com/garyschwitzer

https://twitter.com/healthnewsrevu

Comments

Michael F. Mirochna, MD posted on November 23, 2012 at 10:29 am

How about option 4? Informing patients about the actual numbers and letting them decide? We could offer comparisons to other screening tests. We now can do that with prostate cancer… about 1400 men screened over 10 years with 48 treated for cancer to prevent one prostate cancer related death, but it doesn’t prevent death overall (which is the catch that if not explained well to patients, will end up making them more confused). That’s not even mentioning the sepsis/hospitalizations that will occur just from the biopsy or the morbidity/mortality from surgery either.

It will take time to tear down the dogmatic/rhetoric built wall of early diagnosis = saved lives AND to instill the idea that bad things can and DO assuredly happen with screening.

Thank goodness for smart docs like Dr. Welch to help the cause.

Greg Pawelski posted on November 23, 2012 at 10:48 am

I posed this question over at Dr. Len’s blog:

It’s interesting that this study, by the Avon Comprehensive Breast Center at Massachusetts General Hospital in Boston, has come out at this time. What if combining standard digital mammography with tomosynthesis can significantly decrease false positive recall rates? According to the results of a new multi-center study published in the journal Radiology, the use of three-dimensional (3D) breast imaging, known as tomosynthesis, could improve diagnostic accuracy.

According to the NCI, as many as 30 percent of breast cancers are not detected by mammography and an additional 10 percent of women who undergo a screening mammogram are recalled for further testing when no cancer is present (false positive result). Breast tomosynthesis captures multiple, low-dose images from different angles around the breast. The images are then used to produce a three-dimensional reconstruction of the breast.

The study involved 1,192 women recruited from five sites, of whom 997, including 780 screening cases and 217 women who needed pre-biopsy breast imaging, had complete data sets. Each of the women underwent a standard ditital mammogram followed by breast tomosynthesis. The total raidaiton dose for the combined procedure was less than 3 milligray, which is the FDA limit for a single mammogram.

The use of both tomosynthesis and standard mammogram resulted in increased diagnostic accuracy. Additionally, the diagnositc sensitivity of the combined modality were attributable to the improved detection and characterization of invasive cancers, which are the cancers most concerned about because of their potential to metastasize. False positive recall rates also significantly decreased. According to the researchers, the type of reduction in recall rate can translate into a substantial number of unnecessary diagnostic tests being avoided.

DHN posted on November 26, 2012 at 9:35 am

Great study, and wonderful feedback.

One important additional point on mammography: 600,000 women have been enrolled in randomized trials of screening mammography and no overall mortality benefit is apparent after more than a decade of follow-up, see the Cochrane review. (Overall mortality is the only scientifically trustworthy outcome in such data). In other words, RCTs have shown that mammography doesn’t save lives, and Gil Welch knows this. His brilliant new study is simply an attempt to remind everyone, using a different logic, that the science on mammography is in—it doesn’t work.

Jennifer posted on November 29, 2012 at 3:24 am

Mammography is a huge industry, and those who own these money-making profit centers have no interest in developing an improved screening method. Mammograms may be a blunt instrument but hey, they bring women in every year, and they diagnose plenty of false positives, resulting in more follow-up mammograms. It’s like printing money. Oncology is also an enormously profitable industry. Both groups are fighting any attempt to separate the large group of “patients” whose cancers can safely be ignored, as well as from that unfortunate group of patients whose cancers cannot be cured no matter how early that cancer is caught, from the relatively small group of patients who are actually helped by screening and treatment. Just follow the money. It’s really sad.

    Judy Aiken posted on November 29, 2012 at 11:00 am

    Excellent post. Notice that those attacking studies like this are almost always those who have a vested interest in keeping mammography going, like radiologists, oncologists, etc. Other that or they are women speaking from their emotions who claim their lives were “saved” by mammography when that may have had a “cancer” that never would have bothered them in their lifetime. Thank you to Dr. Welch and the other doctors who have the courage to tell the truth.

Lisa Leger posted on November 30, 2012 at 3:49 pm

Related to this – check out the move by Health Canada to slap thermography down all of a sudden. Out of nowhere? I doubt it.
http://www.hc-sc.gc.ca/ahc-asc/media/advisories-avis/_2012/2012_178-eng.php