ACS: The breast cancer screening debate continues

I am sitting here wringing my hands that so much has been made of some studies reported recently at a major radiology conference which suggest that the impact of the breast cancer screening guidelines released by the United States Preventive Services Task Force (USPSTF) in November 2009 has either been good or bad on doctor and patient behavior.

The reason I am doing the handwringing thing is because I don’t think either study is particularly good at answering the question for which it was intended: have health professionals changed their screening recommendations to their patients as a result of those guidelines, or does it make a true difference in outcome for women between the ages of 40-49 who forgo screening mammograms?

Yet much is being made of these studies, as though they have some definitive answer to the questions they raised.  In my opinion, they don’t.

Now, be certain to note that I was very much in the midst of the discussion back then when these guidelines were released, which suggested that women between 40-49 should not have routine screening mammograms (yes, that was the wording they used) and should consult with their health professional to determine whether they wanted to be screened or not.  For me, the operative language was “recommends against“, and I made that point very clear.  Many equally expert folks thought then and think today that the available data does support a recommendation for routine screening mammography in women between the ages of 40 and 49.  So, we have a legitimate scientific disagreement and the discussions about that disagreement continue vigorously to this day.

But the key point to me is not who is right and who is wrong.  It is whether new data gives us better insights into the issue, and helps resolve some of the questions.  When studies that are not particularly informative take on a life of their own for the sole purpose of making a headline or allowing one side or the other to hammer home their point, then I believe someone should stand up and take those using such limited science to task.

One of the studies presented consisted of a survey of primary care health professionals at the University of Colorado, and recorded the responses of 50 doctors and nurses who provide primary care at the University as to what they recommended to women about screening mammograms before the guidelines were released in 2009 and what they have done afterwards.

To no real surprise, more of these folks say they discuss the risks and benefits of screening with women in the 40-49 year old age group now than did so before 2009.  (Interestingly, there was no report in the study abstract as to whether risks/harms were even discussed before November 2009.  Frankly, doctors and their patients should discuss risks and harms of every medical procedure, no matter whether or not it is a screening mammogram or any other test).  There were some other categories where it appears from this study that doctors and other health professionals have made some changes in their recommendations to conform more with the USPSTF guideline recommendations.

OK.  So far so good.  But what does this really mean?

First, this is a very small sample size to draw conclusions that suggest what is going on nationwide.  It may be right, but it may be wrong, or it might be different in different parts of the country.  What happens in a medical university may be different than what is happening in other settings.  And there may be other subtle or not-so-subtle influences on who answered the survey (people who are more engaged in a process tend to more readily respond compared to those who are not particularly involved in an issue).  And then there is the issue of recall bias, which means what people think they did a couple of years ago may not be what they did (for example, did doctors REALLY not talk to their patients about the risks of a procedure in the past?).

So, to me, from a “news” point of view that might lead people to think this is a nationwide phenomenon and draw sweeping conclusions-whether they see it as good or bad-would be inappropriate in my personal opinion.

Another paper that was presented examined the stage of diagnosis in women with breast cancer between the ages of 40-49 who had a screening mammogram compared to those who were diagnosed because of symptoms including a lump (which is actually a “sign” of disease, but let’s not quibble here).

Again, to no one’s surprise, the stage of diagnosis for women found through a screening mammogram was earlier when compared to women found through women with symptoms.  After all, that is the reason we do screening mammograms.

The hooker in this study was that the authors concluded that this “presumably (translates) into reduced mortality for this group of women.”  The implication is that the “new” screening guidelines and patients not getting mammograms will lead to more breast cancer deaths because the cancers aren’t found until they cause a symptom or result in a lump.

Now, as I mentioned before, I am not a fan of the USPSTF breast cancer screening guidelines.  But I also understand the issues, and understand the arguments.  Unfortunately, contrary to the news headlines, this study doesn’t begin to address the arguments about whether or not those guidelines are “good” or “bad.”

In a nutshell, critics of routine screening mammograms make the argument that mammography finds many breast cancers that would not go on to cause harm to the patient.  In addition, to find those cancers you need to screen many women who end up not having breast cancer, and a significant fraction of those women end up needing a biopsy or other procedure to prove they don’t have breast cancer.  Finally, you may find a breast cancer early, but if you follow enough women long enough-the critics would say-you don’t see a real decrease in deaths that warrants doing the procedure in the first place. In their minds, based on their interpretation of the data, the juice simply isn’t worth the squeeze.

Others don’t agree, but it is a long leap to take the type of research that made today’s headlines and suggest to the public that these studies answer the question of screening mammography in women ages 40-49 one way or the other.  They don’t and it is not appropriate to suggest that they do-and this comes from someone (me) who believes that screening in that age group is the right thing to do.

Lots of studies get presented in abstract form at national medical meetings.  Some make it to the next stage of publication of the full study in a peer reviewed journal.  And even that is not a guarantee that the study is “correct.”  Unfortunately–in no small part because of the efforts of publicists-these very early abstracts with limited information get picked up by the press and moved onto the national stage without being fully developed.

Remember, we live in an age where 140 characters tell the whole story.  Headlines count, and that’s where most people get their news and information.  If the premise or the research is not complete, the potential for misinforming or misleading the public is very real.

If we are going to have a fair fight about a topic as important as screening mammography, its benefits in reducing the risk of breast cancer deaths, and the risks/harms associated with the procedure, then let’s at least make certain that the information underlying our scare headlines is at least reasonably associated with a meaningful scientific report.

And when the science isn’t good or not ready for “prime time”, let’s have the courage to use our efforts to inform the public wisely and move on to something more worthwhile.

J. Leonard Lichtenfeld is deputy Chief Medical Officer for the national office of the American Cancer Society. He blogs at Dr. Len’s Cancer Blog.

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