title: Characterization of ductal carcinoma in situ on diffusion weighted breast MRI.
abstract: OBJECTIVE
  To characterize ductal carcinoma in situ (DCIS) and its subtypes on diffusion-weighted imaging (DWI).
  
  
  METHODS
  We retrospectively reviewed 74 pure DCIS lesions in 69 women who underwent DWI at 1.5 T (b = 0 and 600 s/mm(2)). Each lesion was characterized by qualitative DWI intensity, quantitative DWI lesion-to-normal contrast-to-noise ratio (CNR), and quantitative apparent diffusion coefficient (ADC). The detection rate was calculated with predetermined thresholds for each parameter. The effects of lesion size, grade, morphology, and necrosis were assessed.
  
  
  RESULTS
  Ninety-six percent (71/74) of DCIS lesions demonstrated greater qualitative DWI intensity than normal breast tissue. Quantitatively, DCIS lesions demonstrated on average 56% greater signal than normal tissue (mean CNR = 1.83  ±  2.7) and lower ADC values (1.50 ± 0.28 × 10(-3) mm(2)/s) than normal tissue (2.01 ± 0.37 × 10(-3) mm(2)/s, p < 0.0001). A 91% detection rate was achieved utilizing an ADC threshold (<1.81 × 10(-3) mm(2)/s ). Non-high-grade DCIS exhibited greater qualitative DWI intensity (p = 0.02) and quantitative CNR (p = 0.01) than high-grade DCIS but no difference in ADC (p = 0.40). Lesion size, morphology, and necrosis did not affect qualitative or quantitative DWI parameters of DCIS lesions (p > 0.05).
  
  
  CONCLUSIONS
  DCIS lesions have higher DWI signal intensity and lower ADC values than normal breast tissue. DWI warrants further investigation as a potential non-contrast MRI tool for early breast cancer detection.
authors.affiliation: Department of Radiology, University of Washington, Seattle Cancer Care Alliance, 825 Eastlake Avenue East, Seattle, WA 98109-1023, USA. hrahbar@uw.edu
authors.forename: Habib
authors.initials: H
authors.lastname: Rahbar
authors.forename: Savannah C
authors.initials: SC
authors.lastname: Partridge
authors.forename: Peter R
authors.initials: PR
authors.lastname: Eby
authors.forename: Wendy B
authors.initials: WB
authors.lastname: Demartini
authors.forename: Robert L
authors.initials: RL
authors.lastname: Gutierrez
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; D001943:Breast Neoplasms / Q000175:diagnosis / Q000473:pathology*; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000175:diagnosis / Q000473:pathology*; D015331:Cohort Studies; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007089:Image Enhancement; D007150:Immunohistochemistry; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D012016:Reference Values; D012189:Retrospective Studies; D012680:Sensitivity and Specificity