Comparison of Diagnostic Performance between Perfusion-Related Intravoxel Incoherent Motion DWI and Dynamic Contrast-Enhanced MRI in Rectal Cancer

Abstract

This study was aimed to determine the diagnostic performance of perfusion-related parameters derived from intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) by comparing them with quantitative parameters from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) based on differentiation grades of rectal cancer. We retrospectively analyzed 98 patients with rectal cancer. Perfusion-related IVIM parameters ( $D^{\ast }$ , $f$ , and $f$ · $D^{\ast }$ ) and quantitative DCE parameters ( $K^{\text{trans}}$ , $K_{\text{ep}}$ , $V_e$ , and $V_p$ ) were obtained by plotting the volume-of-interest on in-house software. Furthermore, we compared the difference and diagnostic performance of all well-moderately and poorly differentiated rectal cancer parameters. Finally, we analyzed the correlation between those DCE and IVIM parameters and pathological differentiation grade. The values of $f$ , $K^{\text{trans}}$ , and $K_{\text{ep}}$ significantly differentiated poor and well-moderate rectal cancers. $K^{\text{trans}}$ achieved the highest area under the curve (AUC) value compared to perfusion-related IVIM and DCE parameters. Furthermore, $K^{\text{trans}}$ showed a better correlation with pathological differentiation grade than $f$ . The diagnostic efficiency of DCE-MRI was greater than perfusion-related IVIM parameters. The $f$ value derived from perfusion-related IVIM offered a diagnostic performance similar to DCE-MRI for patients with renal insufficiency.