The Choice of Region of Interest Measures in Contrast-Enhanced Magnetic Resonance Image Characterization of Experimental Breast Tumors

Center for Pharmaceutical and Molecular Imaging, Department of Radiology, University of California San Francisco, CA 94143, USA.
Investigative Radiology (Impact Factor: 4.44). 06/2005; 40(6):349-54. DOI: 10.1097/01.rli.0000163740.40474.48
Source: PubMed


The objectives of this study were to determine if magnetic resonance (MR) estimates of quantitative tissue microvascular characteristics from regions of interest (ROI) limited to the tumor periphery provided a better correlation with tumor histologic grade than ROI defined for the whole tumor in cross-section.
A metaanalysis was based on 98 quantitative MR image breast tumor characterizations acquired in 3 separate experimental studies using identical methods for tumor induction and contrast enhancement.
The endothelial transfer coefficient (K) of albumin (Gd-DTPA)30 from the tumor periphery correlated (r = 0.784) significantly more strongly (P < 0.001) with the pathologic tumor grade than K derived from the whole tumor (r = 0.604). K estimates, either from the tumor periphery or from the whole tumor, correlated significantly more strongly with histologic grade (P < 0.01) than MR image estimates of fractional plasma volume (fPV) from either tumor periphery (r = 0.368) or whole tumor (r = 0.323).
K estimates from the tumor periphery were the best of these measurable MR image microvascular characteristics for predicting the histologic grade.

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