Prospective Comparison of Gd-EOB-DTPA-Enhanced MRI with Dynamic CT for Detecting Recurrence of HCC after Radiofrequency Ablation

Abstract

Background: We prospectively compared the efficacy of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) with that of dynamic multidetector computed tomography (MDCT) for detection of recurrent hypervascular hepatocellular carcinoma (HCC) after radiofrequency ablation (RFA). Methods: Institutional review board approval and written informed consent were obtained for this multicenter study. Ninety-seven HCC patients treated with curative RFA underwent both Gd-EOB-DTPA-enhanced MRI and dynamic MDCT every 3-4 months. HCC diagnosis was made based on the typical enhancement pattern of HCC on MRI and/or CT by on-site consensus reading. Two blinded observers independently assessed image datasets to compare diagnostic accuracy, sensitivity, specificity, and the areas under the receiver operating characteristic curve (AUROC). Results: Recurrence was observed in 48 of 97 patients. Among these, 22 were diagnosed by both Gd-EOB-DTPA-enhanced MRI and MDCT; the remainder were diagnosed by only one of these 2 modalities. Recurrence was diagnosed in more patients by Gd-EOB-DTPA-enhanced MRI than by MDCT (44 vs. 26 patients, p < 0.001). Patient-based analysis revealed that the accuracy, sensitivity, and AUROC of Gd-EOB-DTPA-enhanced MRI were significantly higher than those of MDCT for both observers (p < 0.005). The AUROC of Gd-EOB-DTPA- enhanced MRI and MDCT was 0.95 and 0.76 for observer 1 and 0.90 and 0.74 for observer 2, respectively. The κ values for MRI and MDCT were 0.83 and 0.70, respectively. Conclusions: Compared with dynamic MDCT, Gd-EOB-DTPA-enhanced MRI had higher diagnostic accuracy and sensitivity for detection of recurrent hypervascular HCC and may be a better tool for following patients after RFA.