European guidelines for breast cancer screening differ from U.S. recommendations

Guidelines on breast cancer screening from the European Commission Initiative on Breast Cancer have important differences from U.S. guidelines, according to a recent synopsis and editorial.

The European Commission Initiative for Breast Cancer Screening and Diagnosis guidelines, also called the European Breast Guidelines, were published Oct. 24 and represent the evidence-based consensus of 28 multidisciplinary members. The guidelines pertain to organized screening programs for women ages 40 to 75 years who are at average risk for breast cancer and address digital mammography and the addition of hand-held ultrasonography, automated breast ultrasonography, or MRI versus mammography alone, as well as screening frequency and decision making in average-risk women with suspicious lesions or with high breast density. A synopsis of the guidelines was published Nov. 26 by Annals of Internal Medicine.

Because the risks may outweigh the benefits, the European Breast Guidelines recommend against annual mammography screening. Screening is not suggested for women ages 40 to 44 years but is suggested every two to three years for women ages 45 to 74 years. For women ages 70 to 74 years, the guidelines recommend screening every three years. Tailored screening with automated or hand-held breast ultrasonography or MRI is not suggested for women with high breast density, and digital breast tomosynthesis and 3D mammography are not recommended for use in population-based organized screening programs. The guidelines do suggest that digital breast tomosynthesis rather than diagnostic mammography be used as a follow-up test for women who have suspicious lesions on screening mammography.

An accompanying editorial said that the European Breast Guidelines “juxtapose and amplify 2 key differences between organized European screening programs and U.S. practices that should be considered (or reconsidered).” First, the editorialists said, less frequent screening is recommended in Europe, possibly because screening mammography in Europe is usually interpreted by two radiologists. Recent technologic advancements may allow such double reading to be possible in the United States, where a single reading is now common practice, the editorialists said, although they stressed that they made this statement with caution.

Second, the European guidelines highlight a need for U.S. breast cancer screening policymakers to standardize the quality and outcomes of diagnostic imaging done after an abnormal screening result, the editorialists said. Because U.S. guidelines, unlike those in Europe, usually stop at the screening stage and responses to abnormal results vary widely, future U.S. recommendations should address the entire screening episode, the editorialists said.

“These new guidelines probably will do little to settle the ongoing debate in the United States over when to start mammography screening, what imaging method to use, and how often to screen,” the editorialists wrote. “However, the European Breast Guidelines do provide insights into how we can use the knowledge gained from organized screening to identify areas and avenues for improving the quality and accuracy of breast cancer screening in the United States.”