Denise Chough MD, Abstract Co-Author: Nothing to Disclose

Christiane Hakim MD, Abstract Co-Author: Nothing to Disclose

Rita Zuley MD, Abstract Co-Author: Nothing to Disclose

Maria Anello DO, Abstract Co-Author: Nothing to Disclose

Jules Henry Sumkin DO, Presenter: Scientific Advisory Board, Hologic, Inc

Evaluating margin status with specimen radiography can be a difficult task.  Our goal was to investigate whether tomosynthesis (3D) of a surgical biopsy specimen added to conventional specimen radiography could improve the accuracy of margin status evaluation.

From 08/23/07 to 04/28/09 an IRB approved study was performed which entailed the collection 120 surgically excised tissue specimens. The 55 specimens which were subsequently proven to harbor malignancy and had satisfactory quality specimen radiography (both 2D and 3D) formed the cohort for an observer performance study. Specimen radiography was performed on a research Dimension tomosynthesis machine (Hologic Inc.) and viewed on a Hologic research workstation. For each view magnification 2D and non-magnification 3D radiography was performed then the specimen was rotated 90 degrees and imaging was repeated. Pathology records were evaluated to identify which specimens had “close margins”. A close margin was defined as malignancy present 2mm or less from the specimen edge. The retrospective reader study included four board certified fellowship trained women’s imagers with experience ranging from 2 years to 22 years who were asked to predict weather the margin was positive or negative based on the 2D images and then asked again after presentation of the 3D images.

The pathology of the specimens consisted of 8 DCIS, 16 IDC, 21 IDC/DCIS, 8 ILC, 1 ILC/ADH, and 1 invasive metaplastic cancer. Of the 55 specimen cases pathology revealed that 28 had positive margins and 27 had clear margins. For all readers combined the sensitivity for 2D alone was 45% and the specificity 78%. For 2D+3D the sensitivity was 43% and the specificity 84% which was not a statistically significant difference in either sensitivity (p=0.79) or specificity (p=0.29).

Specimen radiography was better at predicting a negative margin than a positive one. Specimen tomosynthesis in combination with standard 2D images did not significantly improve reader performance. With improved quality of 3D specimen radiographs including magnification and with more experience in interpreting 3D specimen images, performance may improve.

Specimen tomosynthesis did not significantly improve either sensitivity or specificity in evaluating margin status.

Chough, D, Hakim, C, Zuley, R, Anello, M, Sumkin, J, Comparison of 2D Specimen Radiography to 2D Specimen Radiography Plus Specimen Tomosynthesis.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11034302.html