3-D mammograms are better at detecting breast cancer and reducing the need for follow-up tests than conventional screening methods, according to a new study by researchers at the Perelman School of Medicine at the University of Pennsylvania.

The findings, published online in JAMA Oncology, indicate 3D testing — also known as Digital Breast Tomosynthesis (DBT) — provide the first conclusive evidence that that patients who undergo the technique are less likely to be called back for unnecessary imaging in the future.

What’s more, researchers found more cancer cases are found in those patients who are recalled after DBT and fewer breast cancers are diagnosed between regularly scheduled screening appointments in women who receive a clean bill of health after DBT.

In 2011, the U.S. Food and Drug Administration approved use of DBT, which provides radiologists a 3-D view of overlapping layers of breast tissue, in combination with standard digital mammography for breast cancer screening.

For the new study, the Penn team analyzed 44,468 screening mammography examinations of 23,958 women performed at Penn's Perelman Center for Advanced Medicine between 2010 and 2014.The women initially received DM only, but the three consecutive years after the practice converted from DM to all DBT in which all women received a DBT of two-view DM and two-view DBT of each breast.

"These findings reaffirm that 3D mammography is a better mammogram for breast cancer screening," said lead researcher Dr. Emily F. Conant, chief of Breast Imaging in the department of Radiology at the Perelman School of Medicine. "These results are an important step toward informing policies so that all women can receive 3D mammography for screening."

The study was funded, in part, by the National Cancer Institute.