Edwin Jason Yau MD, Presenter: Nothing to Disclose

Roberta Marie Strigel MD, Abstract Co-Author: Nothing to Disclose

Wendy Burton DeMartini MD, Abstract Co-Author: Nothing to Disclose

Peter R. Eby MD, Abstract Co-Author: Research grant, General Electric Company, Milwaukee, WI Research grant, Johnson & Johnson, Cincinnati, OH

Sue Peacock MSC, Abstract Co-Author: Nothing to Disclose

Constance D. Lehman MD, PhD, Abstract Co-Author: Speaker, General Electric Company Speaker, Koninklijke Philips Electronics NV

Atypical ductal hyperplasia (ADH), atypical lobular hyperplasia (ALH), lobular carcinoma in situ (LCIS) and radial scar (RS) are breast lesions considered “high risk” when identified at needle biopsy due to the 20% or greater risk of associated malignancy at surgical excision. There are sparse data regarding high risk lesions initially identified on breast magnetic resonance imaging (MRI). The goals of this study were to determine the outcomes and imaging features of MRI-detected high risk lesions.

This HIPAA compliant study was approved by our IRB. All cases of lesions initially detected with MRI (January 2003 -May 2007) that underwent subsequent image-guided needle biopsy yielding high risk histopathology (ADH, LCIS, ALH and RS) were reviewed. The frequencies of high risk findings at needle biopsy and of upgrade to malignancy at surgical excision were calculated. MRI features and biopsy methods for upgraded lesions were determined.

482 MRI-detected suspicious lesions in 374 patients underwent image-guided needle biopsy. High risk histopathology was present in 73/482 (15.1%) lesions: 64/482 (13.3%) ADH, 5/482 (1.0%) ALH, 3/482 LCIS (0.6%) and 1/482 (0.2%) RS. For 44/73 lesions, direct correlation between the high risk lesion site and specific pathology at surgical excision was confirmed and 13/44 (29.5%) were upgraded to malignancy. 5/13 (38.5%) lesions were upgraded to invasive cancer and 8/13 (61.5%) to ductal carcinoma in situ. Of the upgraded lesions, all contained ADH on needle biopsy; 11 were initially diagnosed with 9-gauge vacuum-assisted biopsy and two with 14-gauge core needle biopsy. Lesions with non-mass-like enhancement (NMLE) upgraded more frequently (8/20, 40.0%) than did masses (2/19, 10.5%). The most common MRI appearance of lesions found to be malignant was NMLE in a linear distribution.

Our frequency of 15% of high risk histopathology at needle biopsy for MRI lesions is higher than reported in other studies (3-9%), while our rate of ADH upgrade is similar and supports excision of this entity. Upgrade was most commonly encountered in lesions demonstrating linear NMLE on MRI.

Surgical excision is recommended for lesions initially identified with MRI and diagnosed as high risk by needle biopsy. Non-mass-like enhancement lesions have the highest upgrade rate.

Yau, E, Strigel, R, DeMartini, W, Eby, P, Peacock, S, Lehman, C, Frequency, Upgrade Rates, and Characteristics of High Risk Lesions Initially Identified with Breast MRI.  Radiological Society of North America 2008 Scientific Assembly and Annual Meeting, February 18 - February 20, 2008 ,Chicago IL. http://archive.rsna.org/2008/6010969.html