title: MR imaging of the breast in patients with invasive lobular carcinoma.
abstract: OBJECTIVE
  Our objective was to assess the usefulness of MR imaging in patients diagnosed with invasive lobular carcinoma of the breast.
  
  
  METHODS
  Between July 1993 and September 1999, 32 women (33 cases) diagnosed with pure invasive lobular carcinoma of the breast underwent contrast-enhanced MR imaging examination. One woman was excluded because of lack of follow-up. Correlation was made between the mammographic and sonographic findings, the MR imaging findings, and the final pathology results for the remaining 32 cases.
  
  
  RESULTS
  In 18 women who did not undergo excisional biopsy before the MR imaging, MR imaging showed more extensive tumor burden or the detection of the primary lesion that was occult on conventional imaging in seven (38.9%) of 18 women. In nine (50%) of 18 women, MR imaging performed equally as well as mammography and sonography. In one case (5.6%), MR imaging and mammography underestimated disease extent. In another patient (5.6%), MR imaging overestimated tumor burden, although mammography failed to show the cancer. In 14 patients who had excisional biopsy before the MR imaging, residual tumor was shown in eight women (57.1%) with extensive tumor or additional separate foci in five of the eight patients. In two cases (14.3%) that were interpreted as equivocal, residual tumor was shown in both cases on reexcision. In three cases (21.4%), the MR imaging was interpreted as negative, but microscopic tumor was shown around seroma on reexcision. False-positive enhancement was seen in one case (7.1%).
  
  
  CONCLUSIONS
  MR imaging showed more extensive tumor than conventional imaging and affected the clinical management in 16 (50%) of 32 patients with invasive lobular carcinoma.
authors.affiliation: Department of Radiology, The University of Pennsylvania Medical Center, 1 Silverstein Bldg., 3400 Spruce St., Philadelphia, PA 19104, USA.
authors.forename: S P
authors.initials: SP
authors.lastname: Weinstein
authors.forename: S G
authors.initials: SG
authors.lastname: Orel
authors.forename: R
authors.initials: R
authors.lastname: Heller
authors.forename: C
authors.initials: C
authors.lastname: Reynolds
authors.forename: B
authors.initials: B
authors.lastname: Czerniecki
authors.forename: L J
authors.initials: LJ
authors.lastname: Solin
authors.forename: M
authors.initials: M
authors.lastname: Schnall
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D018275:Carcinoma, Lobular / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008327:Mammography; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D014463:Ultrasonography