Overselling cancer tests
Early detection saves lives. That’s the assumption that drives aggressive cancer-screening campaigns. It’s what persuades women to host “mammogram parties” where they gather friends for wine, cheese, massages, and breast-cancer screenings. It’s what persuades men to offer up blood for prostate-cancer tests at hockey games or onboard a huge red bus parked at sporting-goods stores.
But the big red bus and other direct-to-consumer screening efforts raise big red flags, our experts say. For one, those campaigns may not be entirely altruistic. In exchange for snacks and door prizes, the radiology clinics and hospitals often behind the campaigns benefit from a new crop of paying customers. Zero, the nonprofit group that offers free prostate-cancer screening at events around the country, counts among its partners doctors and businesses that can benefit financially from cancer testing and treatment.
But most important, the message that you have nothing to lose and everything to gain from being screened—that is, to be tested for a cancer before you have any symptoms of it—simply isn’t true.
“The medical and public-health community has systematically exaggerated the benefits of screening for years and downplayed the harms,” says H. Gilbert Welch, M.D., a professor of medicine at the Dartmouth Institute for Health Policy and Clinical Practice in Lebanon, N.H.
In a recent article in the New England Journal of Medicine, Welch found that the number of early breast-cancer cases had shot up since mammography became common three decades ago but that advanced cancer cases hadn’t declined much. Welch estimated that in 2008 more than 70,000 women 40 and older were found to have small, nonaggressive cancers that were treated even though they probably wouldn’t be life-threatening.
Such treatment, including radiation or the surgical removal of the breast, can cause serious complications. And even when it doesn’t lead to treatment, screening can lead to unnecessary biopsies, which can cause anxiety and pose a small risk of infection.
“When it comes to screening, most people see only the positives,” says Otis Brawley, M.D., chief medical officer of the American Cancer Society. “They don’t just underestimate the negatives, they don’t even know they exist.”
Of course, for some tests, the benefits clearly do outweigh the risks. “My family’s experience illustrates how screening can make all the difference,” says Tracy Doss, an educational assistant in Austin, Texas. Doss lost her father and a grandfather to colon cancer but probably won’t develop the disease herself, because doctors found and removed precancerous growths using colonoscopy.
But for many other tests, the benefits and risks are more evenly balanced, with the final decision depending on a thorough conversation between patient and doctor.
“The marketing message that early detection saves lives is simple and compelling,” says Laura Nikolaides, M.S., director of research and quality-care programs at the National Breast Cancer Coalition. “But the reality as we understand it today is much more nuanced. The problem is how to get that more complex message to the public when it’s so different than what they’ve come to believe.”
For this investigation, we pored over reams of research, consulted medical experts, surveyed more than 10,000 readers, and talked with patients. We found that too many people are getting tests they don’t need or understand, and too few are getting those that could save their lives. Many patients, and even some doctors, can be confused by cancer screening.