Michael J. Michell MBBCH, Presenter: Nothing to Disclose

Asif Iqbal MBBS, Abstract Co-Author: Nothing to Disclose

Rema Wasan MBBCH, Abstract Co-Author: Nothing to Disclose

Abdel Douiri PhD, Abstract Co-Author: Nothing to Disclose

David Evans MD, Abstract Co-Author: Nothing to Disclose

Clare Peacock MBBS, Abstract Co-Author: Nothing to Disclose

Juliet Claire Morel, Abstract Co-Author: Nothing to Disclose

Christopher Peter Lawinski MPhil, Abstract Co-Author: Nothing to Disclose

To assess whether the use of Digital Breast Tomosynthesis (DBT) would overcome the limitations of conventional film-screen and two dimension digital mammography (2DM).

After obtaining ethics approval, all women recalled for further assessment for a mammographic abnormality following routine film-screen mammography were invited to participate in the study. 93.3 % (517/554) clients enrolled in phase-I trial. Each patient underwent bilateral two view cranio-caudal and medio-lateral-oblique 2DM and DBT mammography using Hologic Selenia Dimensions machine. The 2DM and DBT images were acquired during the same compression for each view. 6 specialist radiologists reviewed the cases randomly assigned in a side-by-side, one-after-another unblinded comparison. Receiver-operative-characteristic (ROC) analysis was used to evaluate the results. Sub-analysis was performed for mammographic features and parenchymal density.

22.4%(116/517) cases were malignant. Of these 116 cancers, 88(75.8%) were invasive and 28(24.1%) were in-situ lesions. The diagnostic accuracy of DBT was significantly better than that of film and 2DM, as reflected by a mean (± SE) Area under the Curve (AUC) of 0.967 ± 0.007 for DBT, of 0.912 ± 0.015 for 2D digital and of 0.837 ± 0.025 for film (difference in AUC between DBT and 2D digital, 0.055; 95 % CI, p = 0.0001) and (difference in AUC between DBT and film, 0.13; 95 % CI, p = 0.0001). The performance of DBT was similar in detection of cancers with radiographically fatty, dense or glandular breasts. Analysis according to signs for soft tissue lesions showed that DBT was significantly better than 2DM and film-screen (0.990, 0.941 and 0.871 respectively, p = 0.0002). However for micro-calcification, there was no significant difference for DBT compared to 2DM (0.7896 and 0.7593 respectively, p = 0.0605).

DBT is more accurate in mammographic interpretation than 2DM and film-screen mammography for the whole study group and soft tissue lesions. The phase-II blinded trial will assess differences in detection and specificity between DBT and 2DM and inter-reader variability.

Breast tomosynthesis reduces the problem of tissue superimposition and thereby improves both the sensitivity and specificity of mammography in diagnosis and screening.

Michell, M, Iqbal, A, Wasan, R, Douiri, A, Evans, D, Peacock, C, Morel, J, Lawinski, C, Phase I Trial to Determine the Performance of Digital Breast Tomosynthesis versus Two Dimension Digital and Film-Screen Mammography.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9009317.html