Discrimination of Benign and Malignant Breast Lesions by Using Shutter-Speed Dynamic Contrast-enhanced MR Imaging

Abstract

Purpose:To assess the accuracy of the shutter-speed approach compared with standard approach dynamic contrast materialenhanced magnetic resonance (MR) imaging pharmacokinetic analysis for breast cancer diagnosis. Materials and 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 fi ndings 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 contrastenhanced 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 fi ndings 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 signifi cantly ( P = .008) higher diagnostic specifi city than standard approach K Conclusion: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 fi ndings.q RSNA, 2011Supplemental material: http://radiology.rsna.org/lookup /suppl

Breast DCE-MRI

“…Our study evaluated effects of post-contrast timing only on select semi-quantitative kinetics features; timing effects may be more significant for other diagnostic variables such as quantitative metrics obtained by DCE-MRI pharmacokinetics analysis. More advanced DCE-MRI approaches to improve diagnostic performance for evaluating breast lesions are an area of active research (21), and recent results have shown promise for achieving accurate pharmacokinetic modeling with shortened acquisitions (22). Further, distinction of benign and malignant lesions is primarily dependent on morphological characteristics (5), which our study did not evaluate as these features are typically assessed in the early dynamic phase within 2 minutes after contrast injection and therefore not impacted by choice of delayed phase scan timing.…”

Magnetic Resonance in the Detection of Breast Cancers of Different Histological Types

“…It can also be used to monitor neovascularization of tumors and this can be further quantified using pharmacokinetic modeling of tracer distributions 28–30. In the past, the specificity of DCE-MRI ranged from 37%–91% 31,32.…”

Imaging vascular function for early stage clinical trials using dynamic contrast-enhanced magnetic resonance imaging

“…If a one-compartment model fits the data well there may be no case for using a more complex model; however, in vascular tumours measured at high temporal resolution a poor fit is likely as a onecompartment model may not model the vascular component [75]. More elaborate PK models may improve evaluation of dynamic data and better characterise physiological parameters and biological effects [76][77][78][79][80][81][82][83][84], but are not yet supported by sufficient evidence to warrant use as primary endpoints.…”