Asif Iqbal and colleagues will present findings on Thursday from a study they conducted that included 517 women recalled for further assessment following conventional mammography exams.
Each of the women had a bilateral two-view mammography exam -- both digital and film-screen -- as well as a DBT exam; the study used a Selenia Dimensions unit from Hologic (Bedford, MA). Images were taken during the same compression for each view, and six radiologists interpreted the cases randomly assigned in a side-by-side, one-after-another unblinded comparison.
Of the 517 cases, 116 (22.4%) were malignant, and of these 116 malignancies, 88 (75.8%) were invasive and 28 (24.1%) were ductal carcinoma in situ.
Iqbal's team found that the diagnostic accuracy of DBT was better than that of both digital and film-screen mammography. The mean area under the curve for each modality was:
- 0.967 ± 0.007 for DBT
- 0.912 ± 0.015 for digital mammography
- 0.837 ± 0.025 for film-screen mammography
The study also showed that DBT's performance was not affected by breast tissue type: It performed similarly with fatty, dense, or glandular breast tissue. Also, there was no particular difference between digital mammography and DBT in finding microcalcifications.
DBT did prove better at finding soft-tissue lesions than both forms of mammography, Iqbal's team found, concluding that the technology shows promise as a tool in finding these lesions.