Are Women with Low-to-Average Breast Cancer Risk Getting Too Many MRIs?
Women with low-to-average breast cancer risk are getting the bulk of supplemental MRI screenings, despite lack of evidence about benefits.
Since 2007, breast cancer screening with magnetic resonance imaging in conjunction with mammography has been recommended for high-risk women by the American Cancer Society, the American College of Radiology, and the Society of Breast Imaging. Generally, a woman is considered high risk if she has a 20 percent or greater lifetime risk of breast cancer — for instance, if she has two or more first-degree relatives with breast cancer.
However, recent studies suggest that rates of MRI screening may be increasing among women with low-to-average breast cancer risk, for whom benefits remain unestablished. In a new study, a team of U.S. researchers set out to quantify the use of MRI among women who both meet and do not meet the high-risk criteria for supplemental MRI screening. They published their results Dec. 6 in the Journal of General Internal Medicine.
Women who received a screening mammogram at a Breast Cancer Surveillance Consortium facility between 2007 and 2014 were eligible for the study. In total, 348,955 women underwent 1,499 MRI screenings. Approximately 82.9 percent of these MRIs occurred among women who did not meet the high-risk criteria, and 35.5 percent occurred among those considered to have low-to-average breast cancer risk.
The significant number of women with low-to-average risk getting supplemental MRI screening is of concern, because it isn't consistent with professional guidelines and lacks cost effectiveness. The authors speculate that worries about mammography effectiveness or breast density notification laws could explain the increase in MRI screenings. Also, physicians could be influenced by patients' expectations, reimbursement mechanisms and confidence in the clinical effectiveness of MRI.