Mammo debate: Is it time to push the reset button?

Two opinion papers published recently in the Annals of Internal Medicine argue that it's time to start thinking differently about the issues associated with breast cancer and mammography screening, particularly with each side of the breast screening debate bringing up the same arguments based on data from old trials.

In one article, Russell Harris, M.D., of the University of North Carolina, argues that healthcare providers need to move away from a primary focus on breast cancer screening toward "the larger issue of reducing the burden of suffering that breast cancer brings to society." Harris was a member of the United States Preventive Services Task Force (USPSTF) when it made its controversial screening mammography recommendation in 2009.

Harris points out that the recent update of the Canadian National Breast Screening Study should caution us from "tying our hopes to screening as the panacea for reducing the burden of breast cancer." While acknowledging that critics have faulted the Canadian study, and that some of its findings differed from what the USPSTF found when it conducted its meta-analysis for its 2009 recommendation, Harris says the bottom line from both is the same.

"For women aged 40 to 59 years, screening mammography reduced breast cancer deaths, at best, to only a small degree," Harris writes. In addition, overdiagnosis is a real problem, he points out, and represents at least 22 percent of cases of screen-detected invasive cancer.

"If mammography is really not more than a partial answer to the problem of breast cancer, what further action can women take to deal with a disease that seems unpredictable and uncontrollable? The answer lies in reframing the issue," Harris says. For example, clinicians can do more to get their patients to focus on lifestyle changes that have been associated with a reduced risk of breast cancer, such as maintaining a healthy weight and reducing alcohol consumption.

In the other opinion piece, Peter Jüni, M.D., and Marcel Zwahlen, Ph.D. of the University of Bern in Switzerland, argue that it is time to initiate another breast cancer screening trial, particularly since it has been more than 50 years since the first mammography screening trial. They say that the old trials don't reflect the advances in modern breast cancer treatment.

Jüni and Zwahlen suggest there is an uncertainty about how much of a benefit--if any--comes from screening mammography. And even if there is a benefit from mammography, they say, does it outweigh the harms from breast cancer overdiagnosis?

"Endless rehashing of data from old trials cannot provide definitive answers to these questions," Jüni and Zwahlen write. "The only way to know for certain is to initiate a new trial in the era of contemporary screening technologies and breast cancer therapies."

To learn more:
- read the article by Harris
- read the article by Jüni and Zwahlen