Application of three ablative margin assessment techniques for hepatocellular carcinoma in clinical practice: a comparative study.

[OBJECTIVES] To compare the effect of the intra-operative ultrasound fusion imaging (FI), tumor ghost technique, and pre- and post-operative FI technique for assessing the ablative margin (AM) of patients with hepatocellular carcinoma (HCC) undergoing microwave ablation (MWA).

[MATERIALS AND METHODS] This single-center retrospective cohort study collected clinical and imaging data from patients with HCC who underwent MWA between April 2020 and April 2024. The success rates of three techniques were recorded. The factors affecting technical success of tumor ghost technique were analyzed. Operation time and observer consistency for both tumor ghost and pre- and post-operative FI were compared.

[RESULTS] 135 patients (median age, 63 years, interquartile ranges, 52-68 years; 115 men) were enrolled. The technique efficacy rate was 98.5 %, the incidence of local tumor progression (LTP) was 3.7 %, and the early recurrence rate was 32.6 %. The success rates of intra-operative ultrasound FI and pre- and post-operative FI were 96.0 % and 82.7 %, respectively, which were significantly higher than 32.2 % of tumor ghost technique (p < 0.001). Subgroup analysis of tumor ghost technique showed that adjacent to high-risk locations and post-operative imaging modality were significant factors affecting technical success. Tumor ghost technique had a shorter operation time than pre- and post-operative FI technique (32 s vs. 2.6 min, p < 0.001), with Cohen's kappa coefficients of 0.782 (95 %CI: 0.372-1.000) and 0.514 (95 %CI: 0.275-0.753), respectively (p < 0.001).

[CONCLUSIONS] The intra-operative FI is preferred when feasible; pre- and post-operative FI serves as a reliable alternative; tumor ghost technique functions as a rapid adjunctive method. Each of the three methods has its own characteristics, and the appropriate one can be selected for evaluation based on the patient's condition.