Histologic Spectrum of Magnetic Resonance Imaging (MRI) Detected Suspicious Lesions and Its Clinical Impact in Newly Diagnosed Breast Cancer Patients
M Ramineni, DA Chitale. Henry Ford Hospital, Detroit, MI
Background: Pathologic studies have shown that women thought to have localized breast cancer are at increased risk of having occult multifocal carcinoma which may not be detectable by mammography (MG) or ultra-sonography (USG). MRI is being increasingly used for preoperative local staging, especially in women with mammographically dense breast. We sought to determine the histologic spectrum of MRI detected suspicious lesions and its impact on management.
Design: There were 156 MRI guided biopsies performed at our institution from June 2007 to June 2009, 109 of which were in newly diagnosed breast cancer patients. All the slides were reviewed and pertinent pathologic and clinical parameters were recorded. Cases were broadly subclassified on the basis of pathologic diagnosis into three categories: benign, malignant [in-situ ductal (DCIS) or lobular (LCIS), invasive ductal (IDC) or lobular carcinoma (ILC)] and borderline [atypical duct hyperplasia (ADH), atypical lobular hyperplasia (ALH), flat epithelial atypia (FEA)]. Effort was made to determine whether MRI biopsy changed overall management.
Results: There were 109 MRI guided biopsies from 101 newly diagnosed breast cancer patients (76 IDC, 9 ILC, 14 DCIS, 1 LCIS, 1 carcinosarcoma). Out of 109 biopsies, 80 (73.4%) were benign (26 benign breast tissue, 13 fibroadenomas, 13 fibrocystic change, 9 sclerosing adenosis, 8 intraductal papillomas, 5 fat necrosis, 3 stromal fibrosis, 1 each radial scar, lymph node, stromal hyperplasia). 23/109 (21.1%) were carcinomas (15 DCIS, 7 IDC, 1 ILC); 9 of which were detected in the ipsilateral breast, 12 contralateral, 2 bilateral. There were 6 (5.5%) cases with borderline histology (4 ADH, 1 ALH and 1 FEA), 2 detected in the ipsilateral breast, 3 contralateral, 1 bilateral.
Conclusions: MRI detected significant (25.7%) additional occult disease which changed the course of management. These additional findings were found in bilateral breasts (2.8%), ipsilateral breast (10.1%) and slightly more frequently in contralateral breast (12.8%). But false positive (FP) rate was high (73.4%) and there is a need to reduce FP MRI detection. Correlation of histologic features with suspicious MRI findings may help fine tune radiologists interpretations to achieve this goal.
Wednesday, March 24, 2010 9:30 AM
Poster Session V # 28, Wednesday Morning