Fiona Jane Gilbert MD, Presenter: Speaker, Bracco Group Research Grant, GlaxoSmithKline plc Research Grant, General Electric Company

Lorraine Tucker, Abstract Co-Author: Nothing to Disclose

Susan Mary Astley PhD, Abstract Co-Author: Nothing to Disclose

Paula Willsher, Abstract Co-Author: Nothing to Disclose

Stephen W. Duffy, Abstract Co-Author: Nothing to Disclose

To investigate if the benefit of the addition of digital breast tomosynthesis (DBT) to standard digital mammography varies with reader experience in a UK retrospective reading study.

We collected prospective DBT and FFDM reading data on 1,160 women with cancer and 5,900 whose diagnosis was normal or benign. Each case was read 3 ways (FFDM alone; FFDM with DBT; synthetic 2D image with DBT) by different readers from other sites. A total of 24 readers from 6 sites read at least 200 cases in at least one arm. Mammogram experience ranged from 3 – 25 years (median 10) with cases read/annum ranging from 5,000 – 13,000 (median 8,000). Individual performance for each imaging combination was compared. We calculated sensitivities, specificities and ROC curves by reader experience. Matched comparison of cases by reader experience used McNemar methods.  

When we divided reader experience by the median years (10), the FFDM with DBT and synthetic 2D with DBT had significantly greater specificity than 2D alone for those above and below the median (p<0.001). For those with experience less than 10 years, sensitivity was higher for FFDM with DBT (91%, with 95% CI 88-94%) than for FFDM alone (86%, with 95% CI 83-89%), but this did not reach statistical significance (p=0.1). For those with 10 years experience or more, sensitivity was 88% (95% CI 85-91% in both cases) for both FFDM alone and FFDM with DBT. The ROC curves showed a slightly greater improvement for FFDM plus DBT against FFDM alone in those with less than 10 years experience (82% vs 74%, p<0.001) than in those with 10 years or more (79% vs 72%). There were no significant or substantial non-significant differences in sensitivity between synthetic 2D with DBT and FFDM alone.

The addition of DBT to FFDM improves diagnostic accuracy over all categories of reader experience. There is suggestive evidence that the improvement is greater for readers with less experience.

The addition of DBT may have more benefit for less experienced readers.

Gilbert, F, Tucker, L, Astley, S, Willsher, P, Duffy, S, Does the Benefit of the Addition of Digital Breast Tomosynthesis (DBT) Vary with Reader Experience?.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14045490.html