Large Gulf Between European and U.S. Guidelines on Breast-Cancer Screening

By Reuters Staff

November 27, 2019

NEW YORK (Reuters Health) - A new synopsis of the European Breast Guidelines highlights stark differences between U.S. and European screening programs.

The European guidelines were developed by an international panel of 28 multidisciplinary members, who evaluated the quality of the evidence on breast-cancer screening in the context of population-based organized screening programs.

One key difference is that the European guidelines recommend against annual mammography screening given, the panel concluded, that the risks may outweigh the benefit, Dr. Holger J. Schunemann from McMaster University in Hamilton, Canada, and colleagues note in Annals of Internal Medicine, online November 25.

Another key difference is that the European guidelines do not recommend screening in women 40 to 44 years old, but do recommend screening every two to three years in women 45 to 74 years old, note the authors.

In addition, the European guidelines do not recommend tailored screening with automated or hand-held breast ultrasonography or MRI in women with high breast density, nor do they advise digital breast tomosynthesis (DBT) or three-dimensional (3D) mammography for screening. However, the European guidelines do suggest DBT as a follow-up in women recalled due to a suspicious lesion or mammography screen.

Dr. Joann Elmore of the David Geffen School of Medicine in Los Angeles and Dr. Christoph Lee of the University of Washington School of Medicine in Seattle, offer their perspective on what the European guidelines mean for U.S. practice in an editorial published with the synopsis.

While the European breast guidelines "address the diversity among European countries, more than an ocean separates the United States from Europe with regard to screening policies and practices. Although some aspects of the European Breast Guidelines might be less relevant in the United States, given differences in clinical practice, the challenges of supporting an informed screening decision remain the same."

Drs. Elmore and Lee say the less-frequent screening recommended in Europe could be due (in part) to the fact that two radiologists read each mammogram, not just one as in the U.S. And they say it's also worth noting that the false-positive rate is two to three times higher in the U.S. than in some European countries.

The European guidelines are based on a "consideration of evidence as it relates to their practice of biennial or triennial screening with double reading versus the annual screening with one reader, as is typical in the United States," they point out. "With recent technologic advancements, double reading may be feasible in the United States if performed by subspecialty-trained breast imagers using robust teleradiology capabilities, or with emerging artificial intelligence technology used for the second reading."

The other key difference highlighted in the editorial is that U.S. guidelines stop their recommendations at screening, while the European recommendations go further and recommend 3D mammography after a screening abnormality is detected.

"This recommendation," they write, "is a departure from most other screening guidelines, which address only the screening examination. However, we agree that the entire screening episode should be assessed, with recommendations that include appropriate, timely work-up; therefore, the European guideline group's consideration of the full screening episode of care is laudable. Thus, moving forward, the entire screening episode should be addressed in U.S. screening recommendations."

In the end, write Drs. Elmore and Lee, the new European Breast 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. 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."


Ann Intern Med 2019.