Outcomes of conventional transarterial chemoembolization using guidance software for hepatocellular carcinoma in the caudate lobe of the liver

Background : : To evaluate the outcomes of conventional transarterial chemoembolization (TACE) using guidance software for hepatocellular carcinoma (HCC) in the caudate lobe. Methods : : Seventy-two patients with 79 treatment-naïve caudate lobe HCCs were eligible. TACE was performed through feeders not only identified by automated tumor-feeder detection (AFD) functionality but also detected manually. Technical success of TACE was classified into three grades according to 1-week computed tomography findings: entire tumor embolized with a safety margin (5 mm for tumors < 25 mm and 10 mm for tumors < 25 mm) (grade A); tumor embolized without a margin in parts (grade B); and entire tumor not embolized (grade C). Tumor response was evaluated using the modified Response Evaluation Criteria in Solid Tumors. Tumor-feeder detectability by AFD, technical success of TACE, complete response (CR) at 2-4 months, durable CR, and local tumor progression (LTP) rates calculated by the Kaplan-Meier method were compared in each tumor among three subsegments: the Spiegel lobe (SP); paracaval portion (PC); and caudate process (CP). LTP rates between the grade A and B tumors were also compared. Results : : The mean tumor diameter was 18.6 ± 9.9 mm (range, 6-53 mm), and 111 of 129 (86.0%) tumor feeders were detected by AFD. The rates of feeder detectability by AFD, grade A technical success of TACE, CR at 2-4 months, and durable CR in 30 SP, 38 PC, and 11 CP tumors were 71.4%, 93.3%, 93.1%, and 79.3%; 94.8%, 65.8%, 59.4%, and 34.4%; and 76.5%, 63.6%, 80.0%, and 30.0%, respectively. LTP rates of SP tumors were significantly lower than those of PC tumors (P = 0.0044), and the grade B tumors progressed more frequently (P = 0.0012). Conclusion : : AFD could detect 86.0% of tumor feeders in the caudate lobe; however, the feeder detectability, technical success of TACE, and outcomes differed among the three subsegments.