Cone beam computed tomography-guided microwave ablation for hepatocellular carcinoma under the hepatic dome: a retrospective case-control study

BACKGROUND: Microwave ablation (MWA) for hepatocellular carcinoma (HCC) under the hepatic dome is still clinically challenging. This retrospective control study set out to analyze the technical application and clinical benefits of cone beam computed tomography (CBCT)-guided MWA for HCC under the hepatic dome. METHODS: The study analyzed 76 patients with 110 HCC lesions under the hepatic dome from April 2016 to January 2020. The patients were divided into two groups: (I) the CBCT group (n=31), in which iGuide navigation was used for the puncture, and (II) the conventional computed tomography (cCT) group (n=45), in which a navigation tool was not used for the puncture. The primary endpoints were technical success, puncture score, and the rates of complete ablation (CA), complications, and local tumor progression (LTP). The secondary endpoints were tumor-free survival (TFS) and overall survival (OS). RESULTS: In terms of the primary endpoints, the puncture score, occurrence of pleural effusion, and occurrence of right shoulder pain differed significantly between the CBCT group and the cCT group (2.8 vs. 2.2, P=0.002; 12.9% vs. 35.6%, P=0.03; 9.7% vs. 33.3%, P=0.03, respectively). However, the rates of technical success, CA, major complications, and LTP showed no significant differences between the two groups (100% vs. 100%, P>0.009; 0% vs. 0%, P>0.009; 95.6% vs. 89.2%, P=0.30; 4.5% vs. 4.6%, P=0.96, respectively). Regarding the secondary endpoints, the median TFS was 23.0 [95% confidence interval (CI): 19.5–26.5] vs. 22.0 (95% CI: 18.4–25.6) months (P=0.41) and the median OS was 31.0 (95% CI: 21.4–40.6) vs. 33.0 (95% CI: 27.9–38.2) months (P=0.95). CONCLUSIONS: Cone beam CT is a feasible and effective image guidance tool for MWA of HCC under the hepatic dome.