Tomosynthesis Accuracy in Categorizing Breast Lesions

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.