Usefulness of Cone-Beam CT-Based Liver Perfusion Mapping for Evaluating the Response of Hepatocellular Carcinoma to Conventional Transarterial Chemoembolization.

We investigated the cone beam computed tomography (CBCT)-based-liver-perfusion-mapping usefulness during transarterial chemoembolization (TACE) in hepatocellular carcinoma (HCC) to access treatment response and predict outcomes. From October 2016 to September 2018, 42 patients with HCCs scheduled for conventional TACE were prospectively enrolled. Three reviewers evaluated the unenhanced and contrast-enhanced CBCT and CBCT-based-liver-perfusion-mapping of each tumor. Parenchymal blood volume (PBV) was measured. The operator's judgment on the technical results was recorded. Response outcome was determined on follow-up CT or magnetic resonance imaging, according to the modified Response Evaluation Criteria in Solid Tumors. Diagnostic performance for detection of a viable tumor was evaluated using multiple logistic regression with C-statistics. CBCT-based-liver-perfusion-mapping and the maximum PBV of the tumor were significant in multiple logistic regression analysis of response (p < 0.0001, p = 0.0448, respectively), with C-statistics of 0.9540 and 0.7484, respectively. Diagnostic accuracy of operator's judgment was 79.66% (95%CI 69.39%-89.93%). Diagnostic performance of CBCT-based-liver-perfusion-mapping showed a high concordance in three reviewers. The mean PBV of tumor, maximum PBV of tumor, and mean PBV of liver significantly decreased after TACE (each p < 0.001). In ROC curve analysis, the AUC for prediction of residual tumor by the maximum PBV of tumor after TACE was 0.7523, with 80.8% sensitivity and 60.6% specificity.