title: MR imaging features of infiltrating lobular carcinoma of the breast: histopathologic correlation.
abstract: OBJECTIVE
  Our study aimed to correlate the dynamic contrast-enhanced MR appearance of infiltrating lobular carcinoma of the breast with histopathologic findings.
  
  
  METHODS
  We retrospectively reviewed the high-resolution, fat-suppressed and dynamic contrast-enhanced MR images of 13 of 20 women diagnosed with pathologically proven infiltrating lobular carcinoma of the breast. Twelve of the 13 women presented with breast symptoms and underwent mammography. Five of the women also had breast sonography. MR imaging was performed for evaluation of disease extent before the patients underwent modified radical mastectomy (n = 11) or lumpectomy (n = 2). Three experienced radiologists reviewed the MR scans. The tumor pattern types described on imaging were correlated with a detailed analysis of the pathology.
  
  
  RESULTS
  We found three patterns of infiltrating lobular carcinoma on MR imaging. The tumor pattern on imaging correlated with pathologic tumor morphology. We found the following patterns of infiltrating lobular carcinoma: a solitary mass with irregular margins (n = 4) that corresponded to the same appearance at pathology; multiple lesions, either connected by enhancing strands (n = 6) or separated by nonenhancing intervening tissue (n = 2), that correlated with the pathologic appearance of noncontiguous tumor foci, with malignant cells streaming in single-file fashion in the breast stroma or small tumor aggregates separated by normal tissue; and enhancing septa only, which were correlated with the histopathologic appearance of tumor cells streaming in the breast stroma (n = 1).
  
  
  CONCLUSIONS
  Infiltrating lobular carcinoma may be detected on MR imaging as solitary or multiple lesions that correspond to tumor morphology on pathologic examination. The appearance of multiple lesions or of enhancing fibroglandular breast elements on MR imaging is suggestive of infiltrating lobular carcinoma.
authors.affiliation: Department of Radiology, University of California San Francisco, San Francisco, CA 94143-0628, USA.
authors.forename: Aliya
authors.initials: A
authors.lastname: Qayyum
authors.forename: Robyn L
authors.initials: RL
authors.lastname: Birdwell
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Daniel
authors.forename: Kent W
authors.initials: KW
authors.lastname: Nowels
authors.forename: Stefanie S
authors.initials: SS
authors.lastname: Jeffrey
authors.forename: Tony A
authors.initials: TA
authors.lastname: Agoston
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Herfkens
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000473:pathology* / Q000601:surgery; D018270:Carcinoma, Ductal, Breast / Q000473:pathology* / Q000601:surgery; D018275:Carcinoma, Lobular / Q000473:pathology* / Q000601:surgery; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D015411:Mastectomy, Modified Radical; D015412:Mastectomy, Segmental; D008875:Middle Aged; D015203:Reproducibility of Results; D012189:Retrospective Studies; D013997:Time Factors