Women Deserve to Know the Truth 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.

Fueled by “good intentions” (and “economic conflicts of interest” with the multibillion dollar mammogram industry), “many women [are] being given diagnoses of breast cancer” unnecessarily, “producing unwarranted fear and stress and exposing them to treatment” they don’t need. This is the overdiagnosis problem I’ve been talking about: “the detection of pseudodisease”—mammogram-detected “abnormalities” that look like cancer under the microscope. And so, you’re diagnosed with cancer, you’re treated for cancer, but it was just pseudodisease, and would “never progress to [actually] cause symptoms. The “human costs” include “mastectomies and [even] deaths. The chance that a woman will benefit from [mammograms may be] small—[in fact, may be] ten times smaller than the risk that she may experience serious harm in terms of [this] overdiagnosis.

“How many would elect to [go in for a mammogram] if they knew that for every one woman who is notionally saved by early detection, anywhere from 2 to 10 otherwise healthy women are being turned into breast cancer patients [unnecessarily]?”

Well, first of all: “Are patients [even told] about [the possibility of] overdiagnosis by their physicians…?” I mean, it is, after all, “now recognized as the most serious downside of [mammogram] screening.” Well, hundreds were asked, and less than one out of 10 said that they had been informed about it. And, when they were told about it, a little more than half said they wouldn’t agree to screening if it resulted “in more than 1 overtreated person per 1 life saved.” “Wow. That implies that millions of Americans might not choose to be screened if they knew the whole story; however, [90%] do not.”

Most “[w]omen are aware [about] false-positives…and [tend] to view them as an acceptable consequence of [mammograms].” But, “[i]n contrast, most women [were] unaware that screening [could] detect cancers that may never progress.” And, what they don’t know could potentially even kill them.

So, when considering the pros and cons of mammograms, it would be good to consider “total mortality.” Can it actually help you live longer, on average? And, mammograms have not been shown to do that, “and it is therefore misleading to claim that ‘screening saves lives.'”

Theoretically, “[r]outine [mammograms should] increase…a [50-year-old] nonsmoking woman’s overall survival chance from around 96.3%…to 97.1% over 10 years. [But] [t]hese statistics disregard deaths from overdiagnosis.” Deaths from the unnecessary radiation and chemo, “and thus increased mortality from heart disease and other [cancers] that may entirely outweigh the benefit in terms of reduced breast cancer mortality.”

You can’t irradiate the breast without exposing the rest of your chest to radiation—your heart, your lungs—explaining why breast cancer survivors can end up with “significant and marked impairment in cardiopulmonary [heart-lung] function.” “Radiation [treatments] increase…deaths from heart disease by more than 25% and from lung cancer by nearly 80%.” Now, we would accept that risk if we were beating back some deadly cancer, but “[t]he main effect of screening is to produce patients with breast cancer” for which treatment offers zero benefit—since they “would have remained free of breast disease for the rest of their lives” without it, since “[c]ompelling data [suggest] that most overdiagnosed tumors would have regressed spontaneously without treatment.”

“Still, [women] who have had a cancer detected and then removed are likely to feel their life was saved.” But perhaps 10 times more likely their lives were actually seriously harmed, not saved. Ten times more likely you were told you had a cancer that could kill you, but you really didn’t, corralled into the operating room for surgery you didn’t need. Every doctor’s appointment, every sleepless night, all completely unnecessary—yet, you come out as mammograms’ greatest advocate; it saved your life. That’s the crazy thing about mammograms, about PSA testing for prostate cancer; the people who are the most harmed are the ones who claim the greatest benefit.

So, overdiagnosis creates this vicious “cycle…for more overdiagnosis,” because more and more people know someone—”a friend, a family member,…a celebrity—who ‘owes their life’ to early cancer detection.” So, the worse the test is, the more overdiagnosis it causes, “the more popular [it] becomes. The more mammograms harm women, the better they seem to work. The more breasts that are surgically removed completely unnecessarily, the more women swear by it.

Yeah, it’s maybe billions of dollars wasted for nothing that could be spent on doing more for women’s health. But, it’s the human costs; the “[h]arms from breast cancer-screening [may] outweigh the benefits if death caused by treatment is included.” Based on some best- and worst-case scenario estimates, “[f]or every 10 000 women invited for 10 years of [mammogram] screening, 3 to 4 breast cancer deaths [may be] avoided at [the] cost of” around 2 to 9 deaths “from the long-term toxicity of [unnecessary radiation treatments].” Yet, only one in 10 women undergoing mammography said they were ever told about overdiagnosis, even though nine out of 10 thought they had the right to know.

Now, overdiagnosis is not easy to talk about. It’s a sensitive issue, but “[j]ust because communicating with patients [can be] difficult” doesn’t mean that we shouldn’t do it. Informed women deserve no less;” we have an ethical responsibility to let them know.

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Image credit: klbz via pixabay. Image has been modified.

Motion graphics by Avocado Video

• breast cancer
• breast cancer survival
• cancer
• cardiovascular disease
• chemotherapy
• heart disease
• industry influence
• lifespan
• longevity
• lung cancer
• mammograms
• men's health
• mortality
• prostate cancer
• radiation
• surgery
• women's health