Yikes: Study Finds Mammograms Hardly Lower Death Rate, Lead to Many Wrong Diagnoses

Roughly one third of tumors found in routine mammography screenings are "unlikely to result in illness, according to a new study that says 30 years of the breast cancer exams have resulted in the overdiagnosis of 1.3 million American women."

The study, published in the New England Journal of Medicine, claims that the increase in breast cancer survival rates over the last few decades is because of improved therapies and not screenings, and not because of the widespread use of mammograms. In fact, the widespread mammogram usage resulted in overdiagnosis of breast cancer in roughly 70,000 women a year. Which is a problem as being diagnosed with breast cancer is a big fucking deal — think about the cost, anxiety, radiation exposure, false positives, and overtreatment. Yikes.

"Our study raises serious questions about the value of screening mammography," wrote Dr. H. Gilbert Welch, an epidemiology and biostatistics professor at Dartmouth College's Geisel School of Medicine. "It clarifies that the benefit of mortality reduction is probably smaller, and the harm of overdiagnosis probably larger, than has been previously recognized."

The authors reasoned that if screening were to help patients, it must not only find more early-stage cancers - which it has - it must also reduce the incidence of late-stage cancers, because the tumors would have been eliminated when they were small.

But the data found that this was not the case. For every 122 additional breast cancers detected early, the number of late-stage cancers fell by only eight. To the authors, this suggested something other than screening was largely responsible for the drop in breast cancer deaths.

Welch said the gap was even more apparent when they factored in data for women under the age of 40, who are generally too young to get regular mammograms and therefore served as a control group of sorts. The rate of breast cancer deaths for women 40 and over declined by 28% over the 32 years, while deaths for younger women fell by 42%.

Of course, there are plenty of people that doctors and researchers who argue this isn't true.

"This is simply malicious nonsense," said Dr. Daniel B. Kopans, a senior breast imager at Massachusetts General Hospital in Boston. "It is time to stop blaming mammography screening for 'overdiagnosis' and 'overtreatment' in an effort to deny women access to screening."

For his part, Welsh says he's not arguing against access, he just thinks women should be aware of the mammography's shortcomings. He believes the test should be based not on age but on symptoms and risk: "It's women at the highest risk of dying from breast cancer that stand to benefit the most from screening, and they're the least likely to be overdiagnosed."

I'm torn! As someone who has had loved ones die from this god-awful piece of shit disease, I'm all for everyone being tested all the time. But then, consistent misdiagnosis and exposure to stress and radiation isn't a good thing, either. It's a really bad thing. I guess the best plan is to think of your risk level and symptoms and make an individual plan with your doctor. Again: yikes.

Study questions value of mammography screening [LA Times]