Comparable Outcomes of Ultrasound versus Computed Tomography in the Guidance of Radiofrequency Ablation for Hepatocellular Carcinoma

Abstract

Objectives: To compare the efficacy and safety of ultrasound (US) and computed tomography (CT) in the guidance of radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC).

Materials and methods: We retrospectively analyzed consecutive treatment-naïve patients who received curative RFA for HCC from January 2008 to July 2013. Patients were divided into the US group or the CT group according to their RFA guidance instruments. Patients who were only suitable for US- or CT-guided RFA were excluded. Cumulative incidences of and hazard ratios for HCC recurrence were analyzed after adjusting for competing mortality risk.

Results: We recruited a total of 101 patients in the US group and 51 patients in the CT group. The baseline demographic characteristics were not significantly different in both groups. Initial response rates were similar between the two groups (US vs. CT: 89.1% vs. 92.2%, p = 0.54), and complete tumor ablation was finally achieved for all patients. However, more ablations per session were performed in US group (median 2.0 [1.0-3.0] vs. 1.0 [1.0-2.0]; p<0.01). The 1-, 2- and 3-year local tumor recurrence rates (US vs. CT: 13.0%, 20.9%, and 29.2% vs. 11.2%, 29.8% and 29.8%, respectively) and overall mortality rates (US vs. CT: 5.2%, 9.6% and 16.5% vs. 0%, 3.1% and 23.8%, respectively) were not significantly different. In multivariate analysis, tumor characteristics and underlying liver function, but not US or CT guidance, were independent prognostic factors. The complication rates were similar between the two groups (US vs. CT: 10.9% vs. 9.8%; p = 0.71), and there was no procedure-related mortality.

Conclusions: With comparable major outcomes, either US or CT can be used in the guidance of RFA in experience hands.

Fig 1. Local tumor progression and overall tumor recurrence in the US group and the CT group.

(A) Cumulative incidences of local tumor progression. (B) Cumulative incidences of overall tumor recurrence.

Fig 2. Liver-related mortality and overall mortality in the US group and the CT group.

(A) Cumulative incidences of liver-related mortality rates. (B) Cumulative incidences of overall mortality.