BETA
This is a BETA experience. You may opt-out by clicking here

More From Forbes

Edit Story

Cutting Through The Hyped Costs Of Mammograms

This article is more than 8 years old.

Health Affairs has published a paper titled: National Expenditure For False-Positive Mammograms And Breast Cancer Overdiagnoses Estimated at $4 Billion A Year. The loaded headline and article, appearing in an otherwise helpful issue on “Cost & Quality of Cancer Care,” add to falsehoods and media-bashing about the alleged costs of breast cancer screening.

The main problems I see are two. The first is in how the authors define a false positive, which is too liberally. The second is the authors’ estimate that “overdiagnosis” occurs in 22 percent of invasive breast cancers in women between the ages of 40 and 59. These assumptions undermine their calculations of mammography’s tab.

False positives (FPs) are a huge deal in screening analyses, and definitions vary. These authors considered a false positive to be any mammogram that leads to further evaluation, such as additional imaging and possibly a biopsy, in a woman who doesn’t have breast cancer. Based on real, recent data from a nationwide, U.S. insurance company for over 702,000 women between the ages of 40 and 59, these authors identified nearly 78,000 women who had FPs, which came to just over 11 percent.

That’s not such a high fraction, if you think about it, relative to higher numbers that some papers have suggested. And that’s in part because it’s probably closer to the truth for an individual’s decision over a 2-year period, because it only includes real screens (as opposed to theoretical calculations of if a woman got screened annually for 10 years), because it includes for most women only 1 or 2 mammograms, and is more current (the data from the insurer came from 2011-2013). It turns out among the not-so-whopping 11 percent of women with “false positives,” only 29.3 percent had a breast biopsy.

Specifically, the authors report that 22,807 women out of over 702,000 had breast biopsies. If you consider the true FPs, as I do, as only those instances when women suffered biopsies without cancer, the rate falls to 3.2 percent. Not bad.

The costs of a false positive work-ups turn out to be not so high as you might think. From the paper: “The average expenditure per false-positive mammogram, excluding screening cost, was $852.” In addition, the average out-of pocket cost was said to be $200. So we’re talking about just over $1,050 per false positive, on average, including additional imaging and biopsies. As things go in medicine (think of all the administration, or – think of the costs of caring for women with Stage IV disease), that’s not so much.

Next up, the “over-diagnosed” invasive breast cancers: To the best of my knowledge, there has never been a true, pathologically-monitored case of invasive breast cancer that has been shown to be sufficiently low-grade or vanishing that it might be ignored in a woman between the ages of 40 and 59 years. The authors cite two papers, references 2 and 4, to approximate a 22 percent overdiagnosis rate in invasive breast cancer.

But the overdiagnoses in these papers rest on models and calculations. They are theoretical, not observed. There is no proof.

I would say that the rate of overdiagnosis of invasive breast cancer in women between the ages of 40 and 59 years, apart perhaps from those few women who for some reason in that age group are likely to die soon from something else and for that reason should not be screened, is zero.

Going back to the paper's calculations on mammography, in the section called ANNUAL NATIONAL COST OF BREAST CANCER DIAGNOSIS the authors apply the 22 percent “overdiagnosis” to U.S. population with seemingly catastrophic results. They write that: “20,116 women ages 40-59 will be overdiagnosed with invasive breast cancer, incurring a cost of $1 billion.”

But if overdiagnosis of invasive breast cancer does not apply to women in this age bracket, and the rate is 0 rather than 22 percent, then the costs of overdiagnosis drops from $1 billion to zero.

This one changed assumption lessens the total by at least 25 percent, to $3 billion. And if the false positives are indeed lower than 11 percent, the calculation falls further.

What’s still missing in this analysis and offsets the costs of false positives which are not so huge, is the savings from finding cancer early. The authors report an invasive breast cancer rate of 0.4 percent among the insured women. One might ask, how much less is the cost of treating all those ages 40 to 59 years with invasive breast cancers found sooner than later? That answer might turn this around, entirely.

Not surprisingly, the $4 billion figure drew attention in media including NPR, CNBC, an AP story in the Boston Globe and PBS (and elsewhere), MedPage Today and innumerable local TV news affiliates.

Follow me on LinkedInCheck out my website