title: Features of Pure Lobular Carcinoma In Situ on Magnetic Resonance Imaging Associated with Immediate Re-Excision after Lumpectomy.
abstract: OBJECTIVE
  To evaluate imaging features of pure lobular carcinoma in situ (LCIS) on magnetic resonance imaging (MRI) in patients who underwent immediate re-excision after lumpectomy.
  
  
  METHODS
  Twenty-six patients (46.1±6.7 years) with 28 pure LCIS lesions, who underwent preoperative MRI and received curative surgery at our institution between 2005 and 2013, were included in this study. Clinicopathologic features associated with immediate re-excision were reviewed and analyzed using Fisher exact test or the Wilcoxon signed rank test.
  
  
  RESULTS
  Of the 28 lesions, 21.4% (6/28, six patients) were subjected to immediate re-excision due to resection margin involvement by LCIS. Nonmass lesions and moderate-to-marked background parenchymal enhancement on MRI were more frequently found in the re-excision group than in the single operation group (100% [6/6] vs. 40.9% [9/22], p=0.018; 83.3% [5/6] vs. 31.8% [7/22], p=0.057, respectively). The median lesion size discrepancy observed between magnetic resonance images and histopathology was greater in the re-excision group than in the single operation group (-0.82 vs. 0.13, p=0.018). There were no differences in the mammographic or histopathologic findings between the two groups.
  
  
  CONCLUSIONS
  Nonmass LCIS lesions or moderate-to-marked background parenchymal enhancements on MRI can result in an underestimation of the extent of the lesions and are associated with subsequent re-excision due to resection margin involvement.
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.; Department of Radiology, Kangwon National University Graduate School, Chuncheon, Korea.
authors.forename: A Jung
authors.initials: AJ
authors.lastname: Chu
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Nariya
authors.initials: N
authors.lastname: Cho
authors.affiliation: Department of Pathology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: In-Ae
authors.initials: IA
authors.lastname: Park
authors.affiliation: Department of Radiology, Kangwon National University Graduate School, Chuncheon, Korea.
authors.forename: Seong Whi
authors.initials: SW
authors.lastname: Cho
keywords: Breast neoplasms; Carcinoma in situ; Magnetic resonance imaging