9 out of 10 Women Misinformed About Mammograms

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.

“Selling [cancer] screening can be easy,” starts an editorial in the Journal of the National Cancer Institute. “Induce fear by exaggerating risk. [Then,] [o]ffer hope by exaggerating the benefit of screening. And, don’t mention harms [caused by the screening].” This ploy “is especially easy with cancer—no diagnosis is more dreaded. And, we all know the mantra: early detection is the best protection. Doubt it, and someone may suggest you need your head examined.” And, they are not exaggerating.

“Screening can lead to important benefits, but it can also lead to important harms.” And, so, that’s the big challenge: “conveying the counterintuitive idea that screening [doesn’t] always help—and can even be harmful.” Yet, “[s]urveys have shown that most people believe that cancer screening is almost always a good idea and few believe harm [is even] possible.” In patient-education materials, “passing reference[s] to potential harms [may] deceptively [be] “buried [under] a euphoria of benefits.”

The cancer screening test that has been most carefully studied is mammograms. “In the past 50 years, more than 600,000 women have participated in 10 randomized trials… Given this extraordinary research effort, [it’s] ironic that [mammograms] continue…to be one of the most contentious issues within the medical community.” “There are few [things in medicine] that invoke more passion…than mammograms, with both sides, ironically, accusing the media of being in the opposite camp.

But, this contentiousness “is in itself instructive.” I mean, it should tell us something. “For context, “a [single study] involving fewer than 150 men who were followed for less than 2 years was sufficient to convince physicians of the value of treating severe [high blood pressure],” because the benefits were just so obvious; whereas after 10 trials, 600,000 women, the fact that we’re “still debating the…merits of [mammograms] 50 years later suggests that it’s “a close call” between the benefits and harms. But, that’s assuming people are weighing the pros and cons objectively. It may be worse than that, given the multibillion-dollar industries involved, from the mammogram-machine manufacturers to the radiologists that read them.

“Several organizations publish [contradictory] cancer screening recommendations.” Some say mammograms starting at age 40; others say 50. Some say every year; some say every other year, and some say women shouldn’t get them routinely at all. “There is increasing concern” that these disagreements may be arising from “both financial and emotional conflicts of interest.” People can get so invested in their position that they’ve staked out that it kind of clouds their judgement.

“Reasonable experts agree that the body of evidence suggests that there is some benefit to mammography… Although the benefits…have almost certainly been exaggerated, this does not mean that [mammograms don’t] save lives, or that women shouldn’t get [them].” The question is: do the benefits outweigh the risks? That’s a decision each woman has to make for themselves, but they can’t do that without knowing all the facts.

Women are so bombarded with information about mammograms, you’d think women would be “fairly knowledgeable” about it. “Yet nothing is farther from the truth.” Nine out of ten women surveyed “vastly overestimated the benefit[s],” or had no idea. It’s not the women’s fault, though. They’re obviously being misinformed by the system. Most American women didn’t even appear to understand the basic concept of screening, thinking mammograms somehow help prevent you from getting breast cancer in the first place. This “raises doubts” about how well women are being informed. Sounds like “[w]omen are just being told what they should do, but without being given the facts necessary to make informed decisions…As a result of this paternalism and pink ribbon culture, almost all women have a false impression of the benefit of mammography screening… Most surprisingly, those who frequently consulted their physicians and health pamphlets were slightly worse informed.” So, they were like anti-educated by their doctors. And, the problem is that ‘these kinds of inaccurate and exaggerated perceptions” prevent women from making an “informed choice.”

“Misleading women, whether intentionally or unintentionally,…is a serious issue. All of those in the business of informing women about screening should recall that medical systems are for patients, not the other way around.”

“We should not [just blindly] be selling screening. We should be giving people the numbers they need to decide for themselves.” That’s why I created this video series. “The question of whether screening mammography does more harm than good has the potential to shake up the state of [our] medical knowledge [and] alter our views of ethical [medical] practice…The stakes are high in this discourse because women’s lives hang in the balance.”

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Image credit: KOMUnews via flickr. Image has been modified.

Motion graphics by Avocado Video

• breast cancer
• breast cancer survival
• cancer
• industry influence
• mammograms
• National Cancer Institute
• women's health