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

PURPOSE: 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).

METHODS: We enrolled 16 patients with 21 hepatic lesions treated by IRE and examined by CEUS and CECT at 1 day after IRE and by EOB-MRI at 7 days 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.

RESULTS: 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).

CONCLUSION: CEUS was found to be superior to CECT and EOB-MRI for the diagnosis of residual tumor in the subacute phase following IRE.