Dynamic contrast enhanced MR imaging for evaluation of angiogenesis of hepatocellular nodules in liver cirrhosis in N-nitrosodiethylamine induced rat model.

Abstract

To investigate whether dynamic contrast -enhanced MRI (DCE-MRI) can distinguish the type of liver nodules in a rat model with N-nitrosodiethylamine- induced cirrhosis. Liver nodules in cirrhosis were induced in 60 male Wistar rats via 0.01 % N-nitrosodiethylamine in the drinking water for 35-100 days. The nodules were divided into three groups: regenerative nodule (RN), dysplastic nodule (DN), and hepatocellular carcinoma (HCC). DCE-MRI was performed, and parameters including transfer constant (K^trans), rate constant (K_ep), extravascular extracellular space volume fraction (V_e), and initial area under the contrast concentration versus time curve (iAUC) were measured and compared. The highest K^trans and iAUC values were seen in HCC, followed by DN and RN (all P < 0.05). The area under the receiver operating characteristic curve (AUROC) for DN and HCC were 0.738 and 0.728 for K^trans and iAUC, respectively. The AUROC for HCC were 0.850 and 0.840 for K^trans and iAUC, respectively. Ordinal logistic regression analysis showed that K^trans had a high goodness of fit (0.970, 95 % confidence interval, 13.751-24.958). DCE-MRI is a promising method to differentiate of liver nodules. Elevated K^trans suggested that the nodules may be transformed into HCC. • DCE-MRI is promising for differentiating among RN, DN, and HCC • K ^trans and iAUC positively correlated with malignancy degree of liver nodules • Elevated K ^trans suggests that the nodules may be transformed into HCC.