This news release issued on behalf of a prestigious researcher — one said to have “saved more than 1.1 million lives” according to Science Heroes — claims the evidence is in that regular mammograms after age 74 save lives. But does the evidence presented really show that?
This release raises some important points but it also seems to be touting the professional reputation of the study’s senior author (ranked ahead of Jonas Salk in terms of lifesaving prowess!) when it should have devoted more space to cost and limitations, and making a stronger case for the benefits and evidence.
After skin cancer, breast cancer is the most common cancer in women across all races and ethnicities. Some health experts are challenging the stubborn view that more frequent and technically advanced screening is necessary to confront breast cancer, and have become very vocal in educating the public about the harms of over-diagnosis and erroneous diagnosis (false positives).
This release matters now because the study it informs us about indirectly challenges the findings (some might say non-findings) of the newly released US Preventative Services Task Force final recommendations for mammography screening in women. (In a Q&A on the new recs, the USPsTF says about mammograms for senior women: “For women age 75 and older, the evidence of the overall benefit of mammography screening is unclear, and the Task Force is unable to make a recommendation for or against screening.”) This study by Florida Atlantic University looked at Medicare claims data and came out with a recommendation that elderly women should continue to get regular mammograms. We can assume this release, based on a study published in July 2015, came out this week to coincide with and contribute to the discussion about the USPSTF final recommendations.
Does not mention any costs — either direct or societal. And because patients over 74 are typically covered by Medicare, the financial costs to society would be substantial. In addition to covering the cost of screening mammography, Medicare also covers the use of computer-aided diagnosis (CAD) which multiple studies have found to increase the number of false positives.
The release says the study revealed that “black and white women ages 75 to 84 years who had an annual mammogram had lower 10-year breast cancer mortality than corresponding women who had biennial or no/irregular mammograms.”
The implication is, of course, that having a mammogram during those years and receiving treatment for it (surgery, chemotherapy, radiation) lowers the risk of dying from breast cancer.
However, the release doesn’t tell us how many women went on to receive a cancer diagnosis, how many received any treatment and if so, what kind. The study is observational and doesn’t prove that annual mammograms in elderly women extends life.
The release doesn’t mention any harms that might come from more frequent or aggressive screening of older women. As experts at the University of California-San Francisco and Harvard explained following their 2014 review of studies conducted from 1990 to 2014 on risk factors for women 65 and older and the value of mammography for women 75 and older, “Doctors should focus on life expectancy when deciding whether to order mammograms for their oldest female patients, since the harms of screening likely outweigh the benefits unless women are expected to live at least another decade.”
While the release recommends elderly women should continue to receive regular mammograms, it doesn’t point out that this evidence is based on observation, which cannot prove cause and effect. The study itself published in the American Journal of Medicine states that “although the present data are promising, the results are not conclusive.”
The liberal use of statistics such as “1 in 8 women” will be affected and “1 in 25” without qualification earns this release a Not Satisfactory. The release opens with a long list of stats but doesn’t explain for an already worried public that some breast cancers are not deadly. There’s a long-running debate among medical experts that one of the most frequently diagnosed breast cancers — carcinoma in situ (CIS) — shouldn’t necessarily be termed “cancer” because it’s more of precancerous abnormality rather than a definite cancer precursor.
In addition, the first paragraph of the release ends by pointing out that 41% of breast cancer deaths in 2010 occurred in women between ages 65 to 84 but fails to add the important information that many, if not most of those women who died were diagnosed years, if not decades, before ages 65-84. The release leaves the reader with the impression that 41% of breast cancer deaths in 2010 occurred in women diagnosed between ages 65-84.
There is no mention of funders or potential conflicts of interest in the release.
The main alternatives to extending mammograms to this age group are: 1) no mammogram after age 74 or 2) patients/physicians deciding together to have mammograms based on the patient’s history and risk factors. The release should have urged women older than 74 to talk with their healthcare provider about continuing or ending screening. Instead, the first paragraph seems likely to frighten older readers into thinking they definitely need to continue mammograms.
It’s common knowledge that mammograms are widely available. However, most current guidelines cap recommended annual or biannual mammograms at age 74. These recommendations have a direct effect on Medicare and private insurance coverage.
Unlike other studies that are based on surveillance data and “self reports,” as noted in the release, this study looked at Medicare administrative claims filed from 1995 to 2009 to gather data on incidence and mortality rates.
Aside from the fear-inducing litany of statistics found in the first paragraph (addressed under the Disease Mongering criteria), the rest of the release is free of unjustifiable language.