Overdiagnosis

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50-Year Review: Mammography Benefits Oversold, Harms Minimized

(Getty Images)

(Getty Images)

By Nancy Shute, NPR

Two months ago, a widely publicized Canadian study found that mammograms did not reduce breast cancer deaths, but that study was fiercely criticized by the nation’s radiologists as “incredibly flawed and misleading.”

A few weeks earlier, an analysis found that screening all women annually starting at age 40, as the American Cancer Society recommends, costs $6.5 billion more a year more than following the U.S. Preventive Service’s Task Force recommendation that women be screened every other year starting at age 50.

Now, the latest entries — two studies that try to put all the previous research on mammography’s harms and benefits in perspective.

First, researchers at Harvard took a broad look at all the research on mammograms since 1960 — more than 50 years of study. They also looked at evidence on the harms of false positives and overdiagnoses, in which a woman is treated for a cancer that would never have proved deadly. And they reviewed whether current efforts to try to personalize a woman’s cancer risk helped a woman figure out whether it was worth her while to get a mammogram. Continue reading

Cutting Down on Cancer Overdiagnosis: National Panel Weighs In

Ductal carcinoma in situ seen under a microscope. While doctors also call it Stage 0 Breast Cancer, in an article Monday, doctors argue it should no longer be labelled "cancer." (Ed Euthman/Flickr)

Ductal carcinoma in situ as seen under a microscope.  Doctors also call D.C.I.S. “Stage 0 Breast Cancer.” But in an article Monday, a panel of national scientists argue it should no longer be labelled “cancer.” (Ed Euthman/Flickr)

What power does a word have? If the word is “cancer,” for most people it packs a wallop of emotion ranging from general anxiety to abject terror. For the last 30 years, a large industry has grown and developed with a focus on awareness and screening. The goals were laudable: get screened; catch cancer early; early diagnosis means patients dodge a death sentence.

There’s just one problem. It’s not working. This notion of screening was dependent upon the understanding of cancer 30 years ago: that cancer started from a tiny seed and steadily grew and spread until – without treatment – it killed the patient.

But today scientists know that not all cancers behave this way. Some are fast-growing, some may grow slowly, but progressively. But others are “indolent,” so slow-growing, they will never cause the patient harm.

So what certain cancer screening tests have wrought (think mammography, PSA tests) is a dramatic increase in diagnosis of early-stage disease without a corresponding decline in death rates from cancer or diagnosis of late-stage disease. Many of these early stage patients are likely “overdiagnosed” and then “overtreated” — for cancers that may never have grown and spread.

“We terrify (women) with D.C.I.S. thinking they have cancer. We could wait six months to see if something changes without making people hysterical.”
Against this backdrop, the National Cancer Institute called together a group of nationally recognized cancer doctors and researchers to review the evidence on overdiagnosis. In a Viewpoint published Monday in JAMA, the panel calls for major changes in the way the medical world classifies and thinks of “cancer” and the way screening programs are designed.

“This article is really critical for laying the ground work for introducing what I hope will be groundbreaking changes in screening and prevention,” said lead author Dr. Laura Esserman, director of the breast care center at UC San Francisco. Continue reading

Are Minority Kids Being Missed In ADHD Diagnosis?

(Getty Images)

(Getty Images)

For years, doctors, teachers and parents have fretted that attention deficit hyperactivity disorder (ADHD) is overdiagnosed and that children are overprescribed the stimulants that treat the brain disorder too often.

But, as EdSource Today reports, that’s not the case in California. According to new data from the National Survey of Children’s Health, California ranks 5th lowest in the country in diagnosis. The national average of children with ADHD is 7.9 percent, but in California, the rate is 5.2 percent.

That 5.2 percent rate may be a low one nationally. But globally, rates vary between 3 and 9 percent, “with the average closer to 5,” Prof. Joshua Israel told EdSource Today.

Still, within ethnic groups in California, the diagnosis rates drop dramatically. Kaiser researchers published data earlier this year which showed white children had a 5.6 percent rate — well in line with global averages. But other groups had much lower ADHD diagnosis rates as follows:

  • Black children: 4.1 percent
  • Latino children:  2.5 percent
  • Asian American children: 1.9 percent Continue reading