The role of functional imaging; DWI, ADC and 18F-FDG PET/CT in the evaluation of HCC treatment response after transarterial chemoembolization

Abstract Background The transcatheter arterial chemoembolization (TACE) is one of the treatment lines for patients with hepatocellular carcinoma (HCC), this study was conducted to assess the role of functional imaging including the DWI, ADC and 18F-2-fluoro-2-deoxyglucose (FDG) positron emission tomography-computed tomography (PET/CT) for detection of residual HCC after TACE as compared to the structural liver imaging reporting and data system (LI-RADS). Results The optimal cut off value of standardized uptake value ratio (SUVmax/liver SUVmean ratio) for detection of residual viable HCC after TACE was 1.09 with 88.9%, 87.5% and 88.6% sensitivity, specificity, and accuracy respectively, a lower diagnostic value was noted in the qualitative visual FDG PET/CT assessment with sensitivity, specificity, and accuracy of 81.5%, 75% and 80% respectively. The sensitivity, specificity, and accuracy of DWI for identification of post-TACE viable HCC were 77.8%, 75%, and 77.1% respectively. The optimal cut off value of ADC for the diagnosis of variable HCC was 1.32 × 10−3 mm2/s with sensitivity, specificity, and accuracy of 81.5%, 75%, and 80% respectively. Conclusions DWI, ADC and FDG PET/CT are effective functional imaging modalities for the evaluation of viable residual HCC post-TACE with comparable findings for the dynamic cross-section imaging.