Does the risk of overdiagnosis mean people should stop getting cancer screenings?
Doctors on both sides of the debate increasingly say patients should weigh all the pros and cons—including their health, age, family history and tolerance for uncertainty—and decide for themselves.
That may sound obvious, but the concept of "shared decision-making" is still relatively new in cancer care. Some hospitals have started programs to implement it.
Proponents say shared decision-making requires doctors to be more candid about the upsides, downsides and unknowns of both screening and treating early-stage cancers.
"We in our health-care conversations have not adequately explained both sides," says Otis Brawley, chief medical officer of the American Cancer Society. For example, he says, mammograms do save lives, but not as many as most people think. For women in their 60s, regular screenings reduce the risk of dying of breast cancer by about 30%. "But 70% of women who were going to die of breast cancer will still die of it," Dr. Brawley says.
Patients often overestimate the lifetime risk of dying of cancer, he says. For prostate cancer and for breast cancer, it's about 2.7%. Put another way, for every 10,000 women in their 60s screened annually for 10 years, between five and 49 breast-cancer deaths will be averted; about 90 women will die of breast cancer anyway and 64 to 194 will be treated unnecessarily, according to a recent analysis in JAMA. An additional 940 will have biopsies that find no cancer.
For some patients, lowering even a small risk of dying of cancer is worth undergoing frequent screening and aggressively treating even low-risk cancers. Many cancer survivors say they are glad their cancer was found early, and don't second-guess if it needed to be caught at all. Some say they'd rather know they have even a low-risk cancer than stop looking and be left to wonder.
"Knowledge is empowering—you don't have to act on it, but you should keep an eye on it," says Gary Bloom of Olney, Md., who was treated for an aggressive papillary thyroid cancer 19 years ago.
Official screening guidelines, meanwhile, are moving away from one-size-fits-all recommendations and are telling patients to consult their doctors.
That takes more time, but doctors say it's the best way to manage uncertain risks and myriad human emotions.
Says dermatologist Brett Coldiron : "The era of paternalistic medicine is over."