The Center for Public Integrity has published a thought-provoking piece with the following premise: “There is no evidence digital mammograms improve cancer detection in older women. But thanks to political pressure, Medicare pays 65 percent more for them.”
“We are living in a time when a lot of medical interventions have been oversold, and [digital mammography] is another one,” said Dr. Russell Harris, a professor and preventive medicine expert at the University of North Carolina School of Medicine. “What’s happened is that the people who make the machines, who benefit by selling newer machines, have triumphed.”
And on that path to triumph, the makers of digital mammography machines had plenty of help. The story behind the rise of digital mammography is a tale of intense industry marketing, direct-to-consumer advertising, political lobbying, and strategic campaign donations to politicians who shepherded beneficial Medicare reimbursement rates through Congress, creating the financial incentive for clinics and hospitals to replace film machines with digital.
In 2009, the U.S. Preventive Services Task Force, which was derided by many radiologists and breast cancer advocates for opposing routine mammograms for women aged 40 to 49, found there is insufficient evidence to assess the benefits or harms of digital mammography, regardless of a woman’s age.
Dr. Ned Calonge, the task force chair, said the group reviewed studies including DMIST and “found no evidence that digital was performing better than plain film” when judged in terms of health outcomes.
The distinction between judging imaging technologies based on patient outcomes rather than cancer detection is not a small one. Mammography proponents have long stressed the role that early detection plays in fighting cancer. But Calonge said it may be untrue that simply finding more cancers earlier equates to improved outcomes for women. It’s not the number of cancers that imaging detects, Calonge said, it’s making sure that they find the correct cancers, adding that all screening tests have benefits and harms.
One of the harms of all mammography tests, Calonge said, is they pick up a certain number of cancers that will never harm a woman, leading to needless biopsies and mastectomies in a certain number of women. He said it remains unclear which test – digital or film – better mitigates those risks. “Rather than embrace the new technology, we need to figure out if it works first,” Calonge said.
You can read GE Healthcare’s response at the end of the story on the Center for Public Integrity website.