Specialists agree that having either a family history of breast cancer or dense breast tissue puts patients at a greater risk of developing breast cancer. Where disagreement persists, however, is what exactly to do with that information.

Some experts believe that providers should implement risk-based mammographic screening for breast cancer, but according to a new study published in the American Journal of Roentgenology, such a system could delay the detection and treatment of a large number of cancers.

As the authors explained, the idea of taking restrictive risk-based approach to breast cancer screening has picked up momentum lately. Advocates saying it would help save limited resources and “allay the purported harms of screening mammography.”

“Such models prioritize mammographic screening for women who are at higher risk for breast cancer because of factors such as family history and dense breast tissue and propose delayed screening initiation or less frequent screening for women at average risk of breast cancer,” wrote lead author Colleen H. Neal, MD, department of radiology at the University of Michigan Health System in Ann Arbor, and colleagues. “Although the primary focus of restrictive risk-based screening is women younger than 50 years old, some authors have suggested that less frequent screening could be applied to older women as well.”

To test the effectiveness of such screening, the authors analyzed data from more than 550 screen-detected breast cancers found in more than 530 patients at a single institution from 2011 to 2014. A team of radiologists who specialize in breast imaging interpreted the mammograms on file and broke the data down based on various criteria.

The authors separated the patients into two groups. Group 1 included the patients with no personal history of breast cancer, which was more than 76 percent of all patients studied. Of those patients, more than 75 percent had no family history of breast cancer and 56 percent had nondense breasts. Group 2 included patients who were 40-49 years of age, which was more than 16 percent of all patients studied. In that group, more than 79 percent of patients had no family history of breast cancer and more than 30 percent had nondense breasts.

“We found that many screen-detected breast cancers occurred in women without family history or dense breast tissue,” the authors wrote. “In 44 percent of patients, neither dense breast tissue nor family history of breast cancer was seen. A restrictive risk-based screening strategy prioritizing screening for women with one or both of these risk factors could have led to delayed breast cancer detection for many patients at our institution.”