title: Discrimination of benign and malignant breast lesions by using shutter-speed dynamic contrast-enhanced MR imaging.
abstract: OBJECTIVE
  To assess the accuracy of the shutter-speed approach compared with standard approach dynamic contrast material-enhanced magnetic resonance (MR) imaging pharmacokinetic analysis for breast cancer diagnosis.
  
  
  METHODS
  This study was approved by the institutional review board and was HIPAA compliant. Informed consent was obtained from 89 high-risk women (age range, 28-83 years) who had 92 suspicious lesions with negative findings at mammography (but visible at MR imaging). Each underwent a research dynamic contrast-enhanced MR imaging examination just prior to a clinical MR imaging-guided interventional procedure. Tumor region of interest (ROI) averaged and (for some) pixel-by-pixel dynamic contrast-enhanced time-course data, together with mean arterial input function, were subjected to serial standard and shutter-speed approach analyses to extract pharmacokinetic parameters, including rate constant for passive contrast reagent transfer between plasma and interstitium (K(trans)) and interstitial space volume fraction, or v(e). Pathologic findings were used as reference standards. Diagnostic accuracy was assessed with receiver operating characteristic analyses.
  
  
  RESULTS
  The pathologic analyses revealed 20 malignant and 72 benign lesions. Positive predictive value of the institutional clinical breast MR imaging protocol was 22%. At 100% sensitivity, ROI-averaged shutter-speed approach K(trans) had significantly (P = .008) higher diagnostic specificity than standard approach K(trans): 86.1% versus 77.8%. The difference in the ROI-averaged K(trans) parameter value, or ΔK(trans) (≡ K(trans) [shutter-speed approach] - K(trans) [standard approach]), had even higher specificity (88.9%). Combined use of ROI analysis and pixel-by-pixel mapping of ΔK(trans) achieved 98.6% specificity at 100% sensitivity.
  
  
  CONCLUSIONS
  The use of the shutter-speed dynamic contrast-enhanced MR imaging method has the potential to improve breast cancer diagnostic accuracy and reduce putatively unnecessary biopsy procedures that yield benign pathologic findings.
  
  
  BACKGROUND
  http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11102413/-/DC1.
authors.affiliation: W. M. Keck Foundation High-Field MRI Laboratory-Advanced Imaging Research Center, Oregon Health & Science University, 3181 SW Sam Jackson Park Rd, Portland, OR 97239, USA. huangwe@ohsu.edu
authors.forename: Wei
authors.initials: W
authors.lastname: Huang
authors.forename: Luminita A
authors.initials: LA
authors.lastname: Tudorica
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.forename: Sunitha B
authors.initials: SB
authors.lastname: Thakur
authors.forename: Yiyi
authors.initials: Y
authors.lastname: Chen
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Morris
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Tagge
authors.forename: Maayan E
authors.initials: ME
authors.lastname: Korenblit
authors.forename: William D
authors.initials: WD
authors.lastname: Rooney
authors.forename: Jason A
authors.initials: JA
authors.lastname: Koutcher
authors.forename: Charles S
authors.initials: CS
authors.lastname: Springer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001941:Breast Diseases / Q000473:pathology*; D001943:Breast Neoplasms / Q000473:pathology; D003287:Contrast Media / Q000493:pharmacokinetics; D003937:Diagnosis, Differential; D005260:Female; D019786:Gadolinium DTPA / Q000493:pharmacokinetics; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008327:Mammography; D008875:Middle Aged; D012372:ROC Curve; D012680:Sensitivity and Specificity
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA