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.

The value of PET/CT combined with complementary MRI in the follow-up of hepatocellular carcinoma after transarterial chemoembolization.

“…While CT was originally the most common imaging modality for monitoring HCC patients after TACE. However, its accuracy can be limited by the following pitfalls: beam-hardening artifacts from highattenuation lipiodol masking intra-lesional viable tumor and the significantly thinner feeding arteries of the residual tumor reducing contrast enhancement of the tumor (7) . FDG PET/CT and MRI are better than CT for detecting hepatic focal lesions (7) .…”

“…Correspondingly, the study performed by Nashi et al, (14) showed that PET/CT had a sensitivity of 74.60%, specificity of 57.54%, PPV of 87.5%, NPV of 90.0% as well as accuracy of 88.2% respectively in the assessment of HCC patients after therapeutic interventions. On the other hand, Abdelrahman et al, (7) established that the sensitivity, specificity, and accuracy of FDG PET/CT for the detection of residual viable tumoral tissue after TACE were 81.5%, 75%, and 80% respectively, whereas Kim et al, (13) reported sensitivity of 87.5%, specificity of 71.4% and accuracy of 80% respectively.…”

“…Thus, this combination of PET/CT together with MRI can play a role in the early detection of intrahepatic tumor recurrence even with small or minimal residual viable tissues facilitating successful retreatment at an early stage which improves the outcome, prognosis and survival rate of patients. Late diagnosis makes retreatment very difficult (7) .…”

Role of ADC Mapping in the Assessment of Therapeutic Response of Hepatocellular Carcinoma in Patients with Post-trans-catheter Arterial Chemoembolization

“…In the study ofAbdelrahman et al 12 The qualitative DWI had aisensitivityiandispecificityof 77.8% and 75% for detecting remnant viable HCC after TACE,irespectively. The quantitative ADC value had a higher sensitivity than the DWI for detecting remnant HCC, with aisensitivityiandispecificityof 81.5% and 75%,irespectively, at an ADC cut off value of 1.32 103 mm 2 /s.…”