Article

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: 4.45). 06/2005; 40(6):349-54. DOI: 10.1097/01.rli.0000163740.40474.48
Source: PubMed

ABSTRACT 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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