Mammograms: Just say no

I’ve had two or three mammograms. The last one was in 2008. I don’t remember why I quit having them. At any rate, I’m glad I did. They’re pretty useless and can be damaging.

In spite of three decades of widespread screening mammography in the US, the breast cancer rate is unchanged. In other words, the number of women who are found to have metastatic breast cancer when they first contact the health system is the same now as it was before we screened for breast cancer. As one breast cancer surgeon said, “If mammography was a treatment, we’d never do it. The effect is too small.” That is, breast cancer screening lowers breast cancer mortality on the order of one person per one thousand over ten years--essentially an insignificant number. A ten-year Canadian study of 6000,000 women, half of which were being screened and half of which were not, found that the mammogram group were just as likely to die as the non-mammogram group. So why bother? The Swiss Medical Board has suggested the screening be halted.

There are plenty of other reasons not to have mammograms, the main one being they lead to false alarms, which then lead to more testing: another mammogram, an ultrasound, an MRI, a biopsy. Among 1000 American women age fifty screened annually for a decade, somewhere between 490 and 670 will have a false alarm, and 70 to 100 will be biopsied to prove they don’t have cancer. Research has shown that the psychological effects of false alarms, such as stress and anxiety, often persist for three years. Not good for your health.

What's more, screenings find cancers that would otherwise not be found—harmless cancers that would never develop into anything serious. It’s true that there are plenty of people who think their lives were saved by screening. As Dr. Gilbert Welch says it’s entirely possible that such people “would have done just as well had their cancer been diagnosed following the appearance of signs and symptoms. It’s also possible they were overdiagnosed: the cancer was never destined to kill them or even make them sick.” Eighty percent of breast lumps are non-cancerous. Seventy percent of breast cancers are found through breast self-exams. At least 30 percent of tumors found on mammograms would go away if you did absolutely nothing. 

You can get as much radiation from one mammogram as you would from 1,000 chest X-rays. I suppose that if the radiation were seriously dangerous, the practice would be curtailed, which, of course, it hasn’t. So maybe it’s safe. But it seems creepy to me. Just leave me out of it.

Update: Here's the latest study (2017) that supports what I have written above.

Next week: Broken sleep is normal

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