Madhavi Raghu MD, Presenter: Nothing to Disclose

Jaime Lynn Geisel MD, Abstract Co-Author: Consultant, Siemens AG

Reni Simov Butler MD, Abstract Co-Author: Nothing to Disclose

Regina J. Hooley MD, Abstract Co-Author: Nothing to Disclose

Melissa Angeline Durand MD, Abstract Co-Author: Nothing to Disclose

Liane Elizabeth Philpotts MD, Abstract Co-Author: Nothing to Disclose

Prior studies have shown that tomosynthesis not only reduces false positives in screening, but also results in better assessment of lesions in the diagnostic setting suggesting that fewer studies may require close imaging follow up. The purpose of this study was to determine the impact of tomosynthesis on the rate of final BI-RADS (BR) assessments in the diagnostic setting over time by comparing rates in the first and second years after the introduction of tomosynthesis at our institution.

A retrospective review of all diagnostic mammograms performed with tomosynthesis over a 12 month period (A:Jan 2012 to Jan 2013) was compared with those performed in the next six month period (B:Jan 2013 to June 2013, ongoing). The rate of final BR assessments (1-5) in both groups was determined. For all BR 3 studies, the mammographic findings (asymmetries, calcifications, masses and architectural distortions (AD)) as well as the rate of ultrasound use were compared between periods A and B.

In period A, 3723 tomosynthesis diagnostic mammograms were performed of which 2533(68%) were categorized as BR 1 or 2, 943(25%) as BR 3, and 247(6.6%) as BR 4,5. In period B, 2170 tomosynthesis diagnostic mammograms were performed of which 1584(73%) were categorized as BR 1,2, 450(21%) as BR 3 and 136(10.1%) as BR 4,5. There was a significant decrease in the rate of final BR 3 assessments from 25% to 21%(p<0.0001) and an increase in the rate of final BR 1,2 from 67% to 73%(p<0.0001), respectively. Amongst the BR3 patients, fewer masses were recommended for follow-up in period B (31% to 24%; p=0.0079) with no significant change in the number of asymmetries (30 to 34%;p=0.08) or ADs (1 to 3.6%;p=0.25). An increased utilization of ultrasound from period A to B from 503/943(53%) to 308/450(68%) was observed.

Tomosynthesis in the diagnostic setting has had a significant impact with continued decrease in the rate of BR 3, particularly for masses, with a concomitant significant increase in the rate of BR 1 or 2. Increase in US use is noted and may be related to improved accuracy of tomosynthesis in the assessment of masses.

Diagnostic mammography with tomosynthesis has resulted in fewer close mammographic follow-up studies and more categorized as benign, thereby reducing costs and patient anxiety and indicating overall improved diagnostic confidence.

Raghu, M, Geisel, J, Butler, R, Hooley, R, Durand, M, Philpotts, L, Tomosynthesis in the Diagnostic Setting: Changing Rates of BIRADS Final Assessment Categories over Time.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14011817.html