Non-enhanced Pattern on Contrast-Enhanced Ultrasound in the Local Efficacy Assessment of Irreversible Electroporation Ablation of Pancreatic Adenocarcinoma

Abstract The objective was to evaluate the diagnostic value of contrast-enhanced ultrasound in the assessment of the local efficacy after irreversible electroporation (IRE) ablation of pancreatic adenocarcinoma 1 mo after ablation. Fifteen patients with pancreatic adenocarcinoma were treated with IRE and then examined by contrast-enhanced ultrasound 1 mo after ablation. The contrast agent was SonoVue. Technical efficacy was assessed at 3 mo after IRE and classified as technical efficiency (TE) and technical inefficiency (TIE). Diagnostic performance was analyzed using a receiver operating characteristic curve. Ten patients were considered as having TE, and five, TIE. Complete non-enhancement was observed in seven ablation zones (70.0%) in the TE group, and peripheral heterogeneous enhancement, in all five ablation zones (100.0%) in the TIE group. The non-enhancement pattern differed significantly between the TE and TIE groups ( p  = 0.026), with significant correlation with technical efficacy ( p  = 0.007). The area under the receiver operating characteristic curve was 0.85 ( p  = 0.008, 95% confidence interval: 0.65–1.05). A non-enhancement pattern using contrast-enhanced ultrasound was useful in the assessment of local efficacy after IRE ablation of pancreatic adenocarcinoma.