Dana Robyn Rausch MD, Presenter: Nothing to Disclose

Jolinda Mester MD, Abstract Co-Author: Nothing to Disclose

To determine the likelihood of detecting an ultrasound (US) correlate to suspicious breast lesions detected by contrast-enhanced breast MR (CEBMR) with pathologic correlation.

We retrospectively reviewed 221 consecutive CEBMR exams performed from July 2003 to March 2005 and those patients who underwent subsequent 'second look' US. This yielded 37 patients with 73 suspicious MR findings according to guidelines established by the ACR-BIRADS MR lexicon and occult to mammography and physical exam. The imaging findings were compared with the pathology results and the pre-MR US. The findings of pre-MR US and post-MR 'second-look' US were compared. Institutional Review Board approval was obtained.

The median patient age was 49 (range, 30-76 years). The median size of MR findings was 0.8 cm (range 0.3 - 8.9 cm). The median size of US occult findings was 0.8 cm (range, 0.3 - 4.7 cm) and of correlative US findings was 1.3 cm (range, 0.4 - 2.9 cm). The pattern of MR enhancement was mass in 46 and nonmass in 27. Of the patients with suspicious MR findings, subsequent US detected a correlate in 26% (19/73) of which 11 (58%) were mass and 8(42%) nonmass enhancing lesions. Malignancy was found in 53% (10/19) of MR lesions with an US correlate of which 8 were invasive (80%) and 2 intraductal (20%) versus 47% (9/19) of MR lesions which were US occult of which 5 (56%) were invasive and 4 (44%) intraductal. A normal pre-MR and post-MR US occurred in 16% (6/37). The detection of an US correlate was greater with mass than nonmass enhancing lesions and was more likely for invasive rather than intraductal carcinoma. Lesions of larger size were more likely to have an US correlate.

MR detected lesions can have correlates on 'second look' US. This is more likely to occur with mass than nonmass enhancing lesions and for invasive than intraductal carcinoma. The likelihood of cancer was slightly greater in lesions detected by MR that had an US correlate than in lesions that were US occult. As there are lesions which are only seen by MR, if US correlates are not identified on 'second look' exam, carcinoma may still be present and tissue sampling is indicated.

Rausch, D, Mester, J, The Role of 'Second-Look' Ultrasound of Suspicious Breast Lesions Detected with Magnetic Resonance (MR) Imaging: A Retrospective Review.  Radiological Society of North America 2005 Scientific Assembly and Annual Meeting, November 27 - December 2, 2005 ,Chicago IL. http://archive.rsna.org/2005/4409519.html