title: Quantitative diffusion imaging in breast cancer: a clinical prospective study.
abstract: OBJECTIVE
  To study the correlation between apparent diffusion coefficient (ADC) and pathology in patients with undefined breast lesion, to validate how accurately ADC is related to histology, and to define a threshold value of ADC to distinguish malignant from benign lesions.
  
  
  METHODS
  Seventy-eight patients (110 lesions) were referred for positive or dubious findings. Three-dimensional fast low-angle shot (3D-FLASH) with contrast injection was applied. EPI diffusion-weighted imaging (DWI) with fat saturation was performed, and ROIs were selected on subtraction 3D-FLASH images before and after contrast injection, and copied on an ADC map. Inter- and intraobserver analyses were performed.
  
  
  RESULTS
  At pathology 22 lesions were benign, 65 were malignant, and 23 were excluded. The ADCs of malignant and benign lesions were statistically different. In malignant tumors the ADC was (mean +/- SEM) 0.95 +/- 0.027 x 10(-3)mm(2)/second, and in benign tumors it was 1.51 +/- 0.068 x 10(-3)mm(2)/second. According to receiver operating characteristic (ROC) curves, we found a threshold between malignant and benign lesions for highest sensitivity and specificity (both 86%) around 1.13 +/- 0.10 x 10(-3)mm(2)/second. For a threshold of 0.95 +/- 0.10 x 10(-3)mm(2)/second, specificity was 100% but sensitivity was very low. Inter- and intraobserver studies showed good reproducibility.
  
  
  CONCLUSIONS
  The ADC may help to differentiate benign and malignant lesions with good specificity, and may increase the overall specificity of breast MRI.
authors.affiliation: Department of Radiology, CHU Saint Pierre, Université Libre de Bruxelles, Brussels, Belgium. erubesova@yahoo.com
authors.forename: Erika
authors.initials: E
authors.lastname: Rubesova
authors.forename: Anne-Sophie
authors.initials: AS
authors.lastname: Grell
authors.forename: Viviane
authors.initials: V
authors.lastname: De Maertelaer
authors.forename: Thierry
authors.initials: T
authors.lastname: Metens
authors.forename: Shih-Li
authors.initials: SL
authors.lastname: Chao
authors.forename: Marc
authors.initials: M
authors.lastname: Lemort
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000473:pathology*; D003287:Contrast Media / Q000008:administration & dosage; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D019786:Gadolinium DTPA / Q000008:administration & dosage; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008875:Middle Aged; D011446:Prospective Studies; D012372:ROC Curve; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; C064925:gadodiamide; D019786:Gadolinium DTPA