Multimodality imaging to assess immediate response following irreversible electroporation in patients with malignant hepatic tumors.

Abstract

To assess the diagnostic accuracy of contrast-enhanced ultrasound (CEUS), contrast-enhanced multiphase CT (CECT), and gadoxetic acid-enhanced MRI (EOB-MRI) in identifying residual tumor in the subacute follow-up of patients with malignant hepatic tumors treated by irreversible electroporation (IRE). We enrolled 16 patients with 21 hepatic lesions treated by IRE and examined by CEUS and CECT at 1day after IRE and by EOB-MRI at 7days after IRE. Follow-up examinations by EOB-MRI or CECT and CEUS were performed at 3-month intervals. Two radiologists independently reviewed the images and assessed the probability of residual tumor using a five-point scale with receiver operating characteristic (ROC) curve analysis. The sensitivity and specificity were also evaluated. Verifiable local recurrence was assessed using follow-up imaging as the reference standard. The mean area under the ROC curve was significantly higher for CEUS (0.980) than for CECT (0.742, P<0.01) and EOB-MRI (0.806, P<0.01), as were the sensitivity and specificity (mean 85.7 and 85.7% for CEUS, respectively, vs 64.3 and 46.4% for CECT and 78.6 and 64.3% for EOB-MRI). CEUS was found to be superior to CECT and EOB-MRI for the diagnosis of residual tumor in the subacute phase following IRE.