Tomosynthesis Accuracy in Categorizing Breast Lesions

October 11, 2016
Diagnostic Imaging Staff

Breast lesion categorization compared between tomosynthesis and 2D mammography.

Tomosynthesis used in diagnosis allows for more accurate categorization of breast lesion images, according to a study published in Radiology.

Researchers from Yale University School of Medicine in New Haven, CT, performed a retrospective study to evaluate the effect of tomosynthesis in diagnostic mammography on the Breast Imaging Reporting and Data System (BI-RADS) final assessment categories over time.

The researchers reviewed all diagnostic mammograms obtained during a 12-month interval at their facility and for three consecutive years after. They were grouped as tomosynthesis year 1 (2012), tomosynthesis year 2 (2013), and tomosynthesis year 3 (2014). The rates of BI-RADS final assessment categories 1 to 5 were compared between the 2D and tomosynthesis groups.

The results showed that 2D mammography plus tomosynthesis produced 58.7% negative or benign cases (BI-RADS category 1 or 2) compared with 75.8% with tomosynthesis at year 3. A reduction in the percentage of probably benign (BI-RADS category 3) final assessments also went from 33.3% with 2D mammography compared with 16.4% with tomosynthesis at year 3. The rates of BI-RADS 4 or 5 assessments did not change significantly with tomosynthesis (8.0% with 2D mammography versus 7.8% with tomosynthesis at year 3), but there was a significant increase in the PPV3 (29.6% versus 50%, respectively). These trends increased during the three years of tomosynthesis use.

“Tomosynthesis in the diagnostic setting resulted in progressive shifts in the BI-RADS final assessment categories over time, with a significant increase in the proportion of studies classified as normal, a continued decrease in the rate of studies categorized as probably benign, and improved diagnostic confidence in biopsy recommendations,” the researchers concluded.