Evaluation of tumor angiogenesis using dynamic enhanced magnetic resonance imaging: comparison of plasma vascular endothelial growth factor, hemodynamic, and pharmacokinetic parameters

Abstract

Purpose: To assess whether tumor angiogenesis of breast cancers can be predicted on the basis of dynamic magnetic resonance imaging (MRI). Material and Methods: Seventy‐one patients with 71 breast cancers underwent Gd‐DTPA enhanced dynamic MRI. Two regions of interest measurements were obtained in the periphery and in the center of the breast cancers. Hemodynamic parameters obtained by dynamic MRI included peak time, contrast enhancement ratio (CE ratio), and washout ratio. The triexponential concentration curve of Gd‐DTPA was fitted to a theoretical model based on compartmental analysis. The transfer constant (or permeability surface product per unit volume of compartment “k”) was obtained using this method. Tumor angiogenesis was assessed by plasma vascular endothelial growth factor (P‐VEGF). Results: The P‐VEGF was positive in 28 of 71 tumors (39%). The CE ratio, washout ratio, and k in the periphery in P‐VEGF positive breast cancers (mean 178%, 18%, and 1.5×10−2 (s−1)) were significantly greater ( P<0.01, P<0.05, and P<0.03)) than those for P‐VEGF negative breast cancers (mean: 151%, 14%, and 1.1×10−2 (s−1)). The peak time in the periphery in P‐VEGF positive breast cancers was more marked than for P‐VEGF negative breast cancers, but this difference was not significant. Conclusion: The hemodynamic and pharmacokinetic analysis of MRI provides valuable information about angiogenesis of breast cancers.