For years, women who turn 40 have been told by their doctors that they’ve reached the age at which they have earned a new rite of passage – the yearly mammogram. Ever cautious against the unrelenting threat of breast cancer, women have been told that this one exam could be the difference between life or death in the battle against the theoretical breast cancer that their body may be harboring. Increased funding to breast cancer research and advocacy organizations like Susan G Komen Foundation have turned breast cancer into an impending threat for every woman, further raising awareness of the need for mammograms.
Given the “pervasiveness” of breast cancer and the emphasis on mammography, the medical community was shocked when in 2009, the US Preventative Services Task Force recommended that women before the age of 50 forgo routine annual mammograms, and the decision to pursue mammography should be tailored to the individual patient and discussed with her physician. Those recommendations have largely been ignored by physicians and their patients, as advocacy organizations like the American Cancer Society and physician organizations blasted the task force, claiming it was abandoning women and preaching a dangerous lesson for preventative medicine.
What will likely be hailed as a landmark study was released by the British Medical Journal this week, and unless you’ve only been paying attention to the Sochi Olympics and the winter storm, you probably heard a thing or two about the study.
To quote the New York Times, “One of the largest and most meticulous studies of mammography ever done, involving 90,000 women and lasting a quarter-century, has added powerful new doubts about the value of the screening test for women of any age.” The study randomized nearly 90,000 Canadian women between the ages of 40 and 59 to undergo either yearly mammogram and clinical breast examination or just clinical breast examination alone. The purpose of the study was to see if cancers that couldn’t be felt on exam (nonpalpable) were clinically important or not; if you couldn’t feel the cancer, would it actually kill you?
The researchers claim the results show that clinically non-palpable cancers don’t actually matter much, with an equal number of women dying from breast cancer in both groups. They go on to say that not only did mammogram fail to yield a survival advantage, but that the women who underwent yearly mammograms were also subjected to an increased number of unnecessary interventions, including surgery, radiation, and chemotherapy as well as psychosocial stress.
The notion that mammography isn’t as helpful as originally thought is not a new one. Researchers, public health experts, and physicians have for years thought that the importance of mammography has diminished as newer treatments for breast cancer have emerged, making detecting early stage breast cancers less important. It turns out that many cancers grow slowly or not at all; many women may likely to die from other conditions before the cancer would ever become relevant. Some cancers even shrink or disappear on their own. the problem is that once detected, no one really knows if the cancer will actually be life-threatening.
Given all the attention that breast cancer receives, this new study is unlikely to sway the opinions of many women and their health care providers. But could it be that mammography is being overperformed, subjecting countless women to unnecessary treatments? We learned that PSA testing for prostate cancer ultimately proved to be overutilized… is mammography next? Certainly, the study provides one more piece of evidence for the US Preventative Services Task Force to mull over when they next meet to discuss breast cancer screening. It certainly should make every woman pause… and ask their doctor.