Detection of Recurrent/Residual Hepatocellular Carcinoma: Single-Center Retrospective Comparative Study Between Parenchymal Blood Volume Mapping Using Cone Beam CT and Multiphase Dynamic CT

Purpose: To evaluate the usefulness of cone beam computed tomography (CT)- based parenchymal blood volume (PBV) mapping for the detection of marginal recurrence or residual hepatocellular carcinoma, after transcatheter arterial chemoembolization (TACE), and to compare it with multiphase dynamic CT (MDCT). Materials and Methods: From March 2015 to October 2016, 26 patients with 49 iodized nodules who underwent TACE and a pre-interventional MDCT scan were enrolled in our study. We evaluated the diagnostic efficacies of PBV mapping using cone beam CT and MDCT in the detection of marginal recurrences or viable tumors. Results: The sensitivity, specificity, positive predictive value, and negative predictive value (NPV) of PBV mapping and MDCT were 100%, 96.7%, 94.7%, and 100%, and 77.9%, 93.5%, 87.5%, and 87.8%, respectively. The overall sensitivity for identifying local marginal recurrence was higher for PBV mapping than for MDCT (p < 0.005). The performances of PBV mapping and MDCT in the diagnosis of local marginal recurrence were significantly different (p = 0.037, McNemar test). Conclusion: Compared with MDCT, PBV mapping can significantly increase the detection of marginal recurrence or residual tumor after TACE because it is free of beam-hardening artifact. PBV mapping should be considered as a feasible modalityrelated tool for patients who have undergone chemoembolization.