Effectiveness of Real-Time CT/MRI-US Fusion Imaging in Thermal Ablation of Ultrasonographically Inconspicuous...

This study aims to compare local recurrence-free survival (LRFS) in patients with de novo HCC treated with thermal ablation (TA) using real-time CT/MRI-US fusion imaging (FI) or ultrasound (US) for needle placement.

This single-center retrospective cohort study included patients with de novo HCC who underwent percutaneous TA between January 2013 and December 2021. US was the preferred image guidance modality for ultrasonographically conspicuous lesions; however, for inconspicuous lesions, FI (US-CT or US-MRI) was used for needle placement. Propensity score matching (PSM) with a 1:1 ratio was applied to balance baseline variables between the US- and FI-guided groups. LRFS, disease-free survival (DFS), and overall survival (OS) were compared before and after matching using the log-rank test. Univariate analyses using Cox regression were used to identify prognostic factors for LRFS.

A total of 117 patients with 157 lesions were ablated using US and FI needle guidance in 100 and 57 tumors, respectively. PSM yielded 40 tumors in both groups. The 1-year LRFS rates were similar across the groups before and after matching (US: 0.82, FI: 0.94 (p = 0.07) and US: 0.87, FI: 0.91 (p = 0.20), respectively). Univariate analysis revealed that only tumor size was a predictive factor for LRFS. Before and after matching, the DFS and OS did not significantly differ between the groups (p > 0.05).

FI-guided needle placement facilitates effective targeting of HCC lesions that are ultrasonographically inconspicuous, yielding LRFS outcomes comparable to those achieved with US guidance for ultrasonographically conspicuous lesions. Level of Evidence 3b, Retrospective Cohort Study.