Breast Cancer Screening Under the New Guidelines
Breast Cancer screening guidelines were revised last year by a group of health experts (US Preventive Services Task Force or USPSTF). Based on a systematic review of published evidence, they recommended women at average risk in the age group 50 to 74 have screening mammograms every two years instead of annually. For women in the age group 40 to 49, they left it up to the woman and her doctor to determine screening based on her risk factors and harm versus benefit preferences. This change sparked a firestorm fueled by proponents of annual mammograms and those concerned that insurance companies would require copayments. The emotionally charged opposition to the recommendations may have left many women confused. As we approach Breast Cancer Awareness month, it is important to revisit this topic and review any new findings.
Recent simulation studies funded by the National Institutes of Health (NIH) have confirmed that screening mammograms once every two years for average risk women in the age group 50 to 74 is most efficient. For these women, screening annually would provide the same benefit but would increase the rates of false positives, benign biopsies and over-diagnosis. This was also true for younger women even if they were at a 2 to 4 fold increased risk. So the question becomes, what should women opting for annual screenings do? One strategy could be to consider supplemental and alternative tests every other year.
While supplemental tests such as ultrasounds do have high false positive rates that result in benign biopsies, it might be a safer option for the “off” years due to the lack of radiation exposure. A recently published modeling study (funded by the National Cancer Institute) has shown that while annual mammogram screening of 100,000 women averts 968 deaths, it can induce 125 cases of breast cancer that lead to 16 deaths. This number doubles for women with large breasts which require extra views resulting in greater radiation exposure. For women with dense breast tissue, a supplemental test strategy would definitely be better since ultrasounds have been known to detect cancers missed by mammography in these women. In an earlier blog, we described an “Inside Out” approach to screening with the Agkura™ Personal Score. This simple blood test is also worth considering by women desiring an annual monitoring test and should discuss it with their doctor. At the end of the day, women should be proactive and aware of the available options so they can make the best decisions for themselves in consultation with their physician.