DBT, synthetic mammography earn high marks in breast cancer screening trial

Implementing digital breast tomosynthesis (DBT) in a breast cancer screening program increases both sensitivity and specificity, according to new research published in Radiology. The authors also observed that synthetic mammography (SM) may be able to replace digital mammography (DM) in breast cancer screening, though more research is needed.

“Several studies implementing DBT in screening used ‘combo mode’ DM + DBT,” wrote Per Skaane, MD, PhD, of the University of Oslo in Norway, and colleagues. “However, use of this mode results in a doubling of radiation dose. SM images are a potential solution to this challenge and require no additional radiation dose.”

The authors studied data from more than 24,000 women who underwent breast cancer screening from November 2010 to December 2012 as part of the Oslo Tomosynthesis Screening Trial. The mean patient age was 59.1 years. Each examination was interpreted with for different reading modes: DM alone, DM and computer-aided detection (CAD), DM and DBT and SM and DBT.

Overall, sensitivity was 54.1 percent for DM alone, 56.2 percent for DM and CAD, 69 percent for SM and DBT and 70.5 percent for DM and DBT. Specificity was 94.2 percent percent for DM alone, 94.2 percent for DM and CAD, 95 percent for DM and DBT and 95.4 percent for SM and DBT. The authors also noted that adding DBT to DM resulted in higher sensitivity than double reading with DM.

“Implementation of tomosynthesis in population-based breast cancer screening program significantly increased sensitivity and specificity,” the authors wrote.

Skaane and colleagues noted that adding CAD to DM did not prove to be effective when screening patients for breast cancer.   

“There have been conflicting reports on the value of CAD,” the authors wrote. “Our study provides another data point. The estimated changes in both sensitivity and specificity were small and nonsignificant.”

SM, on the other hand, did show the researchers that it has potential to provide specialists with significant value.

“The use of SM rather than DM in combination with DBT resulted in little change in either sensitivity or specificity, which indicates that SM might be a viable alternative to DM when using DBT, although additional studies are needed,” they wrote.