Adrienne Rebecca Newburg MD, Presenter: Nothing to Disclose

Chloe Muy-Chou Chhor MD, Abstract Co-Author: Nothing to Disclose

Leng Leng Young Lin BA, MD, Abstract Co-Author: Nothing to Disclose

Jennifer Gillman, Abstract Co-Author: Nothing to Disclose

Jin Ah Kim MD, Abstract Co-Author: Nothing to Disclose

Hildegard B. Toth MD, Abstract Co-Author: Nothing to Disclose

Linda Moy MD, Abstract Co-Author: Nothing to Disclose

Prior studies have shown that MRI-detected malignant lesions are more likely than benign to have sonographic correlates, as are masses and foci compared to NME. The purpose of this study is to determine frequency of US correlate for NME, and to assess malignancy rate for NME with an US correlate versus NME without.

An IRB-approved, retrospective review of 5,837 consecutive breast MRIs performed from 2005-2011 identified 928 NME lesions for which follow-up or biopsy was recommended. Two fellowship-trained breast radiologists evaluated these using 5th edition BI-RADS lexicon to define lesion type, distribution, and internal enhancement pattern. Patient demographics and pathology results, including frequency of malignancy, were recorded. Of the 928 NME lesions, 332(36%) were recommended for second-look US. 284/332 (86%) had the recommended second-look US. 48/332(14%) of lesions did not have recommended second-look US, for reasons including loss to follow-up (29/48, 60%), subsequent surgery (18/48, 38%), and proceeding directly to MRI-guided biopsy (1/48, 2%).

In 64/284(23%), an US correlate was seen. US-guided biopsy was recommended for 43/64(67%) lesions. Of the 43 recommended US biopsies, 39/43(91%) were performed yielding: 7/39(18%) malignancies (4 IDC, 2 ILC, 1 DCIS), 6/39(15%) high risk (HR) lesions or atypia (3 papillomas, 3 atypia), and 24/39(62%) benign. 1/39 (3%) US biopsy was non-diagnostic but ultimately yielded DCIS on MRI biopsy. Pathology was not available for 1/39(3%). Of the remaining 21/64(33%) cases in which a correlate was seen, 4/21(19%) were recommended for surgery/surgical consultation (2 IDC, 1 ILC, 1 papilloma), 4/21(19%) for 6-month follow-up US (no malignancy detected on f/u), and 13/21(62%) for 6-month f/u MRI (no malignancy on f/u). In 220/287(77%) no US correlate was seen. MRI biopsy was performed on 107/220(48%) of these lesions which yielded 13/107(12%) malignancies (3 IDC, 7 DCIS, 3 ILC), 15/107(14%) HR lesions/atypia (3 papilloma, 4 LCIS, 5 radial scar/sclerosing lesion, 3 atypia), and 79/103(77%) benign pathology. 1/15(7%) HR lesion was upgraded at surgery to ILC.

The yield for detecting an US correlate for MRI-detected NME is low (23%) with an 18% rate of malignancy, compared with 12% of NME without US correlate.

All suspicious NME should undergo biopsy, regardless of whether a sonographic correlate is identified.

Newburg, A, Chhor, C, Young Lin, L, Gillman, J, Kim, J, Toth, H, Moy, L, Outcomes of Breast MRI-detected Suspicious Non-mass Enhancement (NME): Correlation with Second-look Ultrasound (US) and Frequency of Malignancy.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14012193.html