Mammogram Recommendations: Why the Conflicting Guidelines?

Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

“For nearly a century, public health organizations, professional associations, patient advocacy groups, academics, and clinicians largely viewed cancer screening as a simple, safe way to save lives.” But these days, even though we’re all looking at the same body of evidence, “[d]iffering interpretations about [the] benefits and harms of [mammograms] has led to conflicting recommendations…that range from intensive [annual] screening starting at age 40 to no [routine] screening at all [ever].” Currently, the four main groups in the U.S. “charged with making [mammogram] recommendations” each set contradictory guidelines. So, what’s a woman to do?

Well, the guidelines are based on “systematic reviews” of the evidence. “In the last 15 years, 50 [such] reviews…have been published,” but they don’t all reach the same conclusions. The question is why? It turns out that the conclusions of systematic reviews may have been influenced by competing conflicts of “interests of the authors.”

“[O]nly in health care [does] the same group that provides a service also [tell] us how valuable that service is and how much of it we need… We must [sadly] acknowledge that just as in any other profession or industry, self-interest is unavoidably at work…” In an analysis of more than a hundred papers, the “imbalance” in those that tended “to emphasize the major benefits of mammography…over its major harms [was] related to the authors’ affiliation.”

It may be no coincidence that all the expert panels that have come out against routine mammograms excluded radiologists, figuring those who depend on mammograms for their paycheck might be more likely to recommend them—to which mammogram proponents respond: “if you don’t have a conflict of interest, you[’re] probably [not doing it right],” accusing the breast cancer-screening panels of “inject[ing] their own biases.” “In this debate, there are armies of the faithful, and only a disappointing scattering of moderators and peacemakers.”

Some have even suggested that we shouldn’t even be talking about this in public, but “[s]uch paternalism assumes that women cannot decide for themselves whether the available evidence supports or refutes the case for mammography. Discouraging a discussion with women about the evidence for and against…[could be considered] more harmful for women’s health, not less, if doctors truly believe that patients should be active partners in making decisions about their [own body].”

Yeah, if you read the actual studies, you can see if the investigators declare any conflicts of interest. But, if you just hear about the studies second-hand, you may have no idea. Until the developers of screening guidelines emphasize “evidence over commercial or financial interests,” we all have to take personal responsibility to become “informed consumers.”

It would be nice to be able to just trust like cancer charities, but “[i]t is virtually impossible” for such organizations to remain strictly “evidence-based” when they must rely on keeping donors happy “for their very existence.”

To his credit, the Chief Medical Officer of the American Cancer Society said that “we need to be true to the science.” But, note this was him talking about prostate cancer screening. See, the American Cancer Society just straight up tells women to get mammograms, but for men, it leaves them to decide for themselves. They’re open about the prostate cancer-screening harms, but “[v]ery little transparent information about the harms of [mammograms] is provided…”

So, there’s this “double standard”; “women are encouraged” to just do it, “while men are advised to” weigh the pros and cons, “although the fundamental issues to consider are [actually] very similar” between the two tests. “The dissimilarity in how [organizations like the American Cancer Society] view” the patients’ role in decision making “couldn’t be clearer. Do [they] believe that men can handle uncertainties regarding screening tests…,” but that women might just get all “confused”? Men get to “make informed decisions” about their bodies, but women are merely “summoned.”

The bottom line is that there is “more than one right answer” to the question: “Should I be screened for breast cancer?” My goal I have for this video series is to enable you to make the decision that is right for you or your loved ones. One survey suggested that if women were fully informed at how small the benefit actually was, 70% wouldn’t do it. But, you may be in that 30%, and have a right to decide for yourself.

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Image credit: Rhoda Baer via Wikimedia. Image has been modified.

Motion graphics by Avocado Video

• breast cancer
• breast cancer survival
• cancer
• industry influence
• mammograms
• men's health
• prostate cancer
• women's health