As I write this, I am attending the 2014 meeting of the American Association for Cancer Research (AACR, Twitter hashtag #AACR14) in San Diego. Basically, it’s one of the largest meetings of basic and translational cancer researchers in the world. I try to go every year, and pretty much have succeeded since around 1998 or 1999. As an “old-timer” who’s attended at least a dozen AACR meetings and presented many abstracts, I can see various trends and observe the attitudes of researchers involved in basic research, contrasting them to that of clinicians. One difference is, as you might expect, that basic and translational researchers tend to embrace new findings and ideas much more rapidly than clinicians do. This is not unexpected because the reason scientists and clinical researchers actually do research is because they want to discover something new. Physicians who are not also researchers become physicians because they want to take care of patients. Because they represent the direct interface between (hopefully) science-based medicine and actual patients, they have a tendency to be more conservative about embracing new findings or rejecting current treatments found not to be effective.
While basic scientists are as human anyone else and therefore just as prone to be suspicious and dismissive of findings that do not jibe with their scientific world view, they can (usually) eventually be convinced by experimental observations and evidence. As I’ve said many times before, the process is messy and frequently combative, but eventually science wins out, although sometimes it takes far longer than in retrospect we think it should have, an observations frequently exploited by advocates of pseudoscience and quackery to claim that their pseudoscience or quackery must be taken seriously because “science was wrong before.” To this, I like to paraphrase Dara O’Briain’s famous adage that just because science doesn’t know everything doesn’t mean you can fill in the gaps with whatever fairy tale that you want. But I digress (although only a little). In accepting the validity of science that indicates either that a medical intervention that was commonly used either doesn’t help, doesn’t help as much as we thought it did, or can even be harmful, they have to contend with the normal human reluctance to admit to oneself that what one was doing before might not have been of value (or might have been of less value than previously believed) or that, worst of all, might have caused harm. Or, to put it differently, physicians understandably become acutely uncomfortable when faced with evidence that the benefit-risk profile of common treatment or test might not be as favorable as previously believed. Add to that the investment that various specialties have in such treatments, which lead to financial conflicts of interest (COI) and desires to protect turf (and therefore income), and negative evidence can have a hard go among clinicians.
There are times when the best-laid blogging plans of mice and men often go awry, and this isn’t always a bad thing. As the day on which so many Americans indulge in mass consumption of tryptophan-laden meat in order to give thanks approached, I had tentatively planned on doing an update on Stanislaw Burzynski, given that he appears to have slithered away from justice yet again. Then what to my wondering eyes should appear in my e-mail in box but news of a study that practically grabbed me by my collars, shook me, and demanded that I blog about it. As if to emphasize the point, suddenly e-mails started appearing by people who had seen stories about the study and, for reasons that I still can’t figure out after all these years, were interested on my take on the study. Yes, I realize that I’m a breast cancer surgeon and therefore considered an expert on the topic of the study, mammography. I also realize that I’ve written about it a few times before. Even so, it never ceases to amaze me, even after all these years, that anyone gives a rodential posterior about what I think. Then I started getting a couple of e-mails from people at work, and I knew that Burzynski had to wait or that he would be relegated to my not-so-secret other blog (I haven’t decided yet).
As is my usual habit, I’ll set the study up by citing how it’s being spun in the press. My local home town paper seems as good a place to begin as any, even though the story was reprinted from USA Today. The title of its coverage was Many women receiving unnecessary breast cancer treatment, study shows, with the article released the day before the study came out in the New England Journal of Medicine:
One issue that keeps coming up time and time again for me is the issue of screening for cancer. Because I’m primarily a breast cancer surgeon in my clinical life, that means mammography, although many of the same issues come up time and time again in discussions of using prostate-specific antigen (PSA) screening for prostate cancer. Over time, my position regarding how to screen and when to screen has vacillated—er, um, evolved, yeah, that’s it—in response to new evidence, although the core, including my conclusion that women should definitely be screened beginning at age 50 and that it’s probably also a good idea to begin at age 40 but less frequently during that decade, has never changed. What does change is how strongly I feel about screening before 50.
My changes in emphasis and conclusions regarding screening mammography derive from my reading of the latest scientific and clinical evidence, but it’s more than just evidence that is in play here. Mammography, perhaps more than screening for any disease, is affected by more than just science. Policies regarding mammographic screening are also based on value judgments, politics, and awareness and advocacy campaigns going back decades. To some extent, this is true of many common diseases (i.e., that whether and how to screen for them are about more than just science), but in breast cancer arguably these issues are more intense. Add to that the seemingly eternal conflict between science and medicine communication, in which a simple message, repeated over and over, is required to get through, versus the messy science that tells us that the benefits of mammography are confounded by issues such as lead time and length bias that make it difficult indeed to tell if mammography—or any screening test for cancer, for that matter—saves lives and, if it does, how many. Part of the problem is that mammography tends to detect preferentially the very tumors that are less likely to be deadly, and it’s not surprising that periodically what I like to call the “mammography wars” heat up. This is not a new issue, but rather a controversy that flares up periodically. Usually this is a good thing.
And these wars just just heated up a little bit again late last week.