Published on the Oct. 20, 2016, DiagnosticImaging.com website
By Whitney L. Jackson
For the past decade, screening mammography has been the widely accepted tool for identifying potential breast cancers as early as possible. But, as diagnosis rates have increased, so have the questions about whether the procedure is pinpointing the right cancers instead of simply more cancers.
In an October New England Journal of Medicine study, H. Gilbert Welch, MD, MPH, professor of medicine of Dartmouth University Geisel School of Medicine, analyzed data from 1975 to 2012 from the Surveillance, Epidemiology, and End Result (SEER) program to determine tumor size and breast cancer incidence in women age 40 and older. He and his colleagues determined the fatality rates for years before screening mammography popularity grew and after.
The number of early-detected small breast tumors spiked from 36% to 68%, while the number of large tumors dropped from 64% to 32%. Examined against the fatality rates, the specter of overdiagnosis loomed. Diagnostic Imaging spoke with Welch about the likelihood of overdiagnosis among women with potential breast cancers and what it means for screening mammography efficacy.
What are the overarching clinical implications of your study?
I think the overarching message is that, with mammography, the clear call is that most people appreciate the potential, but it benefits very few. That’s one reason we emphasize the very good news that reduced breast cancer mortality largely reflects better treatments, not screening. Mammography comes with the human cost of treating others for disease that would never have been a bother to them. That’s the overdiagnosis problem. It’s not limited to breast cancer screening. Radiologists will be familiar with it in the context of early thyroid cancer, lung cancer, or prostate cancer screening. It’s a general problem in cancer screenings.
To read the remainder of the Q&A at its original location: http://www.diagnosticimaging.com/breast-imaging/qa-practice-overdiagnosing-breast-cancer
