Click here to view PDF.Breast Cancer Screening Recommendations:
More evidence or more confusion?By Gary H. Lyman, MD, MPH, FRCP(Edin)
In the current national healthcare reform debate, few issues have generated more opinions and greater confusion than the value of cancer screening such as for prostate and breast cancer. Breast cancer mortality has decreased by 27% since the early 1990s, likely the result of earlier diagnosis with screening and better treatment options. Nevertheless, skepticism has recently been voiced about the value of breast cancer screening, which, along with persistent financial and educational barriers, has led to a decline in mammography screening rates despite clear recommendations from the American Cancer Society and several medical professional organizations.* The federally funded US Preventive Services Task Force (USPSTF) has until now fully supported such recommendations. Mysteriously, and reading somewhat like a John Grisham or Dan Brown novel, the USPSTF has reversed several long-held key recommendations for breast cancer screening. Despite little new data and no change in estimates of benefit and harm, the USPSTF now recommends against screening in the 40- to 49-year age group, screening in older women only every other year instead of annually, and explicitly recommends against teaching women breast self-examination (BSE). So, why has the USPSTF reversed its positions on such important issues that fly in the face of other US recommendations including their own?
A few clinical trials have updated their results, and one new study in the 40- to 49-year age group from the United Kingdom reports an estimated reduction in the risk of breast cancer mortality at 10 years of 17%, virtually identical to that of earlier trials considered by the USPSTF. In fact, in the most recent trial, adjustment for incomplete adherence with screening led to an achievable reduction in breast cancer mortality in women aged 40 to 49 years of nearly 25%. After considering potential harm from false positive results and low-level radiation exposure, the net benefit was found to exceed any harm over a broad range of assumptions.
The USPSTF now considers this reduction in mortality to be “small” in this age group, which they balance against “moderate” potential harm from unnecessary biopsies. Most oncologists would consider a treatment reducing breast cancer mortality by 15% to 25% a breakthrough. While there is no evidence that occasional negative biopsies cost lives, failure to diagnose early-stage breast cancer does. While recent advances have focused on less surgery and a more personalized approach, we are not yet able to safely identify patients with breast cancer who do not require treatment. It is premature and somewhat reckless to suggest that some invasive breast cancers are not life threatening and do not require treatment. The USPSTF now recommends screening older women every 2 years rather than annually. While the clinical trials varied in the screening interval from every year to more than 2 years, it is not possible to directly compare the value or loss of benefit to less frequent screening in those trials. While such a change could save costs in the short term, the additional confusion and uncertainty may lead to further declines in screening rates, while even a small increase in more advanced disease may have an eventual adverse effect on both women’s lives and healthcare costs.
Perhaps the most puzzling change in recommendations from the USPSTF relates to BSE, which, despite no new data, they now explicitly recommend that women NOT be taught. While it is true that two large trials on this subject found no reduction in mortality, they were conducted in very different cultures and health systems and have questionable relevance to a US setting. While the potential for harm and costs are negligible, countless women have found their cancer through self-examination months or even years before it would have likely come to medical attention at a more advanced stage. Why would the USPSTF recommend against patients being taught a simple, safe, and inexpensive procedure that may be life saving? Go figure.
While some will conclude that these misguided recommendations are an early attempt to ration healthcare, they more likely reflect the need for input from practicing cancer specialists with expertise in the diagnosis and treatment of breast cancer. Whatever the cause, these new and conflicting recommendations are likely to lead to greater confusion and reduced breast cancer screening, reversing decades of effort to reduce the devastating impact of advanced breast cancer on the lives of tens of thousands of women in this country each year. Should the Center for Medicare and Medicaid Services and other insurers act on these new recommendations, reversing hard-fought reimbursement policies for breast cancer screening, it will be a major step backward, not forward, in the war against cancer. Efforts to improve the survival and quality of life for women with breast cancer require the rational application of all effective strategies in a cost-effective manner, including breast cancer screening.