Steven P. Poplack MD, Presenter: Research Grant, Hologic, Inc

Tracy Frazee, Abstract Co-Author: Nothing to Disclose

Zhongze Li, Abstract Co-Author: Nothing to Disclose

Elizabeth W. Dann MD, Abstract Co-Author: Nothing to Disclose

Tor Tosteson, Abstract Co-Author: Nothing to Disclose

To compare the diagnostic accuracy of adjunctive Digital Breast Tomosynthesis (DBT) versus Contrast Enhanced Magnetic Resonance Imaging (CEMRI) in determining primary cancer extent and in characterizing the frequency and disposition of additional abnormalities. To assess and compare patient satisfaction of DBT and CEMRI.  

50 consecutive patients with a new breast cancer diagnosis underwent both adjunctive CEMRI and combined 2D/3D DBT.  The adjunctive exams were interpreted by pairs of study readers blinded to the result of the other adjunctive exam but with knowledge of the patient's clinical history and breast imaging.   Readers determined maximum lesion size and finding type of the primary cancer and noted any additional abnormalities.  Findings warranting additional evaluation, underwent diagnostic clinical imaging and were categorized with a final BIRADS assessment.  The disposition of each additional abnormality, including its effect on surgical management, was determined. The gold standard for primary cancer diameter was established by pathologic evaluation of the surgical excision specimen. The mean size difference between DBT and pathologic tumor measurements and CEMRI and pathology were compared using a paired t-test.  A paired t-test was also used to assess patient satisfaction.

On average there was an 8.1mm discrepancy in tumor size for DBT and a 6.9mm discrepancy for CEMRI.  DBT underestimated tumor size while CEMRI over estimated tumor size.  DBT was statistically significantly less accurate.  DBT detected 15 additional lesions, 4 of which were malignant and resulted in a change in surgical management in 3 patients.  CEMRI detected 45 additional lesions, 11 of which were malignant resulting in management change in 9 patients.  Overall the DBT exam was considered more satisfactory to patients than CEMRI.

CEMRI is more accurate in determining local disease extent then DBT.  On average CEMRI detects 3x as many additional lesions as DBT.  A similar proportion of the additional lesions detected by each modality reflects atypical or malignant histology and results in a similar proportional change in management. DBT is more acceptable to patients than CEMRI.

Staging of newly diagnosed breast cancer with adjunctive imaging has the potential to improve surgical management, but the operating characteristics of the adjunctive exam may impact its value.

Poplack, S, Frazee, T, Li, Z, Dann, E, Tosteson, T, A Comparison of Digital Breast Tomosynthesis versus Contrast Enhanced Magnetic Resonance Imaging in the Preoperative Assessment of Breast Cancer.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12032503.html