Ellen Bachman Mendelson MD, Presenter: Scientific Advisory Board, Hologic, Inc Research support, Siemens AG Speakers Bureau, Siemens AG Medical Advisory Board, Quantason, LLC Consultant, Quantason, LLC Speakers Bureau, SuperSonic Imagine Research support, SuperSonic Imagine Medical Advisory Board, Toshiba Corporation

Wendie A. Berg MD, PhD, Abstract Co-Author: Research grant, Naviscan, Inc Researcher, Naviscan, Inc Speaker, SuperSonic Imagine Researcher, SuperSonic Imagine Medical Advisory Board, Koninklijke Philips Electronics NV Author, Gamma Medica Ideas, License, Merge Healthcare

Marina I. Feldman MD,MBA, Abstract Co-Author: Nothing to Disclose

David Owen Cosgrove MBBCh, FRCR, Abstract Co-Author: Research Consultant, SuperSonic Imagine Research Consultant, Bracco Group Speakers Bureau, Toshiba Corporation

Joel Gay, Abstract Co-Author: Employee, SuperSonic Imagine

Claude Cohen-Bacrie, Abstract Co-Author: Executive Vice President, SuperSonic Imagine Officer, SuperSonic Imagine

SWE shows most cancers to be stiff. Our goal was to see if there are SWE predictive color patterns in lesions grouped by Emax as very soft (<30kPa) or relatively soft (<80 kPa) contributing to accuracy of BI-RADS assessments.

From 9/2008 to 9/2010 in 16 centers in the USA and Europe (BE1 Trial, SuperSonic Imagine, Aix-en-Provence, FR)1562 breast masses were evaluated with B-mode ultrasound (US) and SWE. Thresholds of 160 were upgraded to biopsy. From the database, ultrasound (US) images and site-assigned B-mode BI-RADS assessments of each of these pathology-proved soft cancers were reviewed. The placement of ROI's in lesion and background tissue were checked for technical accuracy, and we tallied SWE color overlay patterns including background tissue color, lesion color, hetero- or homogeneity of the color overlay, and presence of a perilesional rim.

367/1562 (23.5%) masses were very soft, with 6 malignant. 470/1562 (30.1%) were relatively soft. Of these, 45 (9.6%) were malignant. Of the 6 very soft cancers, 2 were BI-RADS 4A, or 0.5% of the 367 very soft masses; the other 4 were assessed as BI-RADS 4B-5. Of the 470 relatively soft masses, 45 (9.6%) were malignant, 2 (0.4%) BI-RADS 3, 9 (1.9%) 4A, and 34 (76%) were 4B and higher. Only 5/501(1%) soft cancers (3-4A) and 9/501 4B and higher (1.8%) had classic benign blue mass in homogeneously blue background. All other soft cancers were marked by partial or complete turquoise (lighter blue-green) rims (5 masses in BI-RADS 3-4A & 18 in 4B-5, 23/51 or 45.1% of soft cancers) aound blue or blue-black masses, & most, even small masses <1 cm, had suspicious B-mode features, or "blips," 3 mm focal areas of turquoise or (10 blips in BI-RADS 3-4A and 21 in 4B-5, total 31/51 or 60.8%). Placement of ROI was inconsistent prior to 3/2009, & Emax possibly underestimated.

Most malignant masses are stiff by quantitative elastographic criteria as well as their color depictions. Relatively few cancers are soft, such as some high grade invasive ductal carcinomas, and SWE should not be used to downgrade masses suspicious on BI-RADS feature analysis; turquoise rims and blips can suggest that a soft lesion (Emax < 80 kPa) may require biopsy.

SWE should not be used to downgrade masses that are suspicious based on BI-RADS feature analysis; color heterogeneity and rim patterns may be supportive of BI-RADS assignments of 4B and higher.

Mendelson, E, Berg, W, Feldman, M, Cosgrove, D, Gay, J, Cohen-Bacrie, C, Soft Breast Cancers: Patterns and Pitfalls in Shearwave Elastography (SWE) in the BE1 International Multicenter Trial.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11012434.html