title: Breast MR imaging: computer-aided evaluation program for discriminating benign from malignant lesions.
abstract: OBJECTIVE
  To retrospectively determine the sensitivity of kinetic features measured with computer-aided evaluation at breast magnetic resonance (MR) imaging in discriminating benign from malignant lesions, with histopathologic findings used as the reference standard.
  
  
  METHODS
  Institutional review board approval was obtained for this HIPAA-compliant study. Informed consent was waived. Suspicious breast lesions visible only at MR imaging and in which biopsy had been performed with MR imaging guidance were retrospectively evaluated with a computer-aided evaluation program. Computer-generated kinetic features for each lesion were recorded, and those of benign and malignant lesions were compared. Features analyzed included the presence or absence of computer-aided evaluation "threshold enhancement" at 50% and 100% minimum thresholds; degree of initial peak enhancement; and enhancement profiles composed of lesion percentages of washout, plateau, and persistent enhancement. The Fisher exact test and Student t test were used to assess differences in these analyses.
  
  
  RESULTS
  One hundred fifty-four consecutive lesions (41 malignant, 113 benign) in 125 women (age range, 27-86 years; mean age, 52 years) were evaluated. The presence of threshold enhancement at computer-aided evaluation was sensitive for malignancy, with 38 of 41 (93%) malignant lesions demonstrating enhancement at both the 50% and 100% thresholds. Absence of threshold enhancement at computer-aided evaluation helped improve the discrimination between benign and malignant lesions when compared with that at initial interpretation by the radiologists. False-positive rates were reduced by 8.8% at the 50% enhancement threshold (not significant) and by 23.0% at the 100% enhancement threshold (P=.02) when compared with that at initial interpretation. Analyses of initial peak enhancement values and enhancement profiles did not demonstrate further improvements in lesion discrimination.
  
  
  CONCLUSIONS
  The use of computer-aided evaluation for breast MR imaging significantly helped improve the discrimination of benign from malignant lesions when compared with that at initial interpretations by radiologists.
authors.affiliation: Department of Radiology, University of Washington Medical Center, Seattle Cancer Care Alliance, 825 Eastlake Ave E, Room G3-200, Seattle, WA 98109-1023, USA.
authors.forename: Teresa C
authors.initials: TC
authors.lastname: Williams
authors.forename: Wendy B
authors.initials: WB
authors.lastname: DeMartini
authors.forename: Savannah C
authors.initials: SC
authors.lastname: Partridge
authors.forename: Sue
authors.initials: S
authors.lastname: Peacock
authors.forename: Constance D
authors.initials: CD
authors.lastname: Lehman
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D001943:Breast Neoplasms / Q000473:pathology*; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA