title: Usefulness of diffusion-weighted imaging of breast tumors: quantitative and visual assessment.
abstract: OBJECTIVE
  We evaluated the usefulness of quantitative and visual assessment of diffusion-weighted imaging (DWI) of breast tumors to distinguish malignant from benign tumors.
  
  
  METHODS
  The DWI findings of 106 breast lesions (15 benign, 91 malignant) were retrospectively analyzed. The mean apparent diffusion coefficient (ADC) value for each lesion was calculated using b values of 250, 500, 750, and 1000 s/mm(2) as a quantitative assessment. We visually evaluated the signal intensity of each breast lesion on the basis of a spinal signal intensity in DWI (b = 1000 s/mm(2)) and compared the mean ADC values using a threshold mean ADC +1.65 × standard deviation (SD) for malignant and benign breast lesions. Obviously strong signal intensity of the lesion relative to that of the spinal cord on DWI signifies malignancy.
  
  
  RESULTS
  The mean ADC value for benign lesions (1.50 ± 0.38 × 10(-3) mm(2)/s) was significantly higher than that for malignant lesions (0.98 ± 0.19 × 10(-3) mm(2)/s), with 94.5% sensitivity, 80% specificity, and 92.5% accuracy. Sensitivity for visual assessment was 91.5%, specificity was 33.3%, and total accuracy was 82.5%.
  
  
  CONCLUSIONS
  ADC values, but not visual assessment, may be useful for differentiating benign and malignant breast tumors.
authors.affiliation: Department of Radiology, Saitama Medical University International Medical Center, 1397-1 Yamane, Hidaka 350-1298, Japan. kaiji@saitama-med.ac.jp
authors.forename: Kaiji
authors.initials: K
authors.lastname: Inoue
authors.forename: Eito
authors.initials: E
authors.lastname: Kozawa
authors.forename: Waka
authors.initials: W
authors.lastname: Mizukoshi
authors.forename: Junji
authors.initials: J
authors.lastname: Tanaka
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Saeki
authors.forename: Takaki
authors.initials: T
authors.lastname: Sakurai
authors.forename: Fumiko
authors.initials: F
authors.lastname: Kimura
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000473:pathology; D003287:Contrast Media; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D008875:Middle Aged; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media