[The efficacy and safety of computed tomography-guided percutaneous cryoablation for malignant liver tumors at high-risk sites]

Objective: To assess the efficacy and safety of computed tomography (CT)-guided percutaneous cryoablation in treating malignant liver tumors located explicitly at high-risk sites. Methods: Data were collected retrospectively from patients with malignant liver tumors undergoing percutaneous cryoablation at Tianjin Medical University Cancer Hospital between January 2018 and December 2021. In all, 46 patients with malignant liver tumors at non-high-risk sites were matched 1∶1 according to the maximum tumor diameter. Technical success rate, complete ablation rate, and complications at 12 and 24 months post-surgery were evaluated. A statistical analysis of the ablation effect difference between the high-risk site and non-high-risk site groups was conducted. Univariate and multivariate logistic regression analyses were performed to identify risk factors. Results: Both groups demonstrated a 100% intraoperative technical success rate, and no major complications related to cryoablation were observed. The complete ablation rate was 82.6% (38/46) and 71.7% (33/46) in the high-risk group and 84.8% (39/46) and 73.9% (34/46) in the non-high-risk group at 12 and 24 months, respectively. There was no significant difference in complete ablation rates between the two groups (P>0.05). Multivariate analysis identified the distance between the tumor edge and high-risk site ≤5 mm and preoperative trans-arterial chemoembolization (TACE) treatment as independent risk factors for cryoablation effect. Conclusion: CT-guided percutaneous cryoablation is a safe and effective approach for patients with malignant liver tumor at high-risk sites. Our results emphasize the importance of proper preoperative planning and intraoperative manipulation.