Abstract
Objectives
To identify the predictors of incomplete percutaneous radiofrequency ablation (RFA) of colorectal cancer liver metastases (CLMs) and evaluate the impact of incomplete RFA (iRFA) on the overall survival (OS) of patients and new intrahepatic metastases (NIHM).
Methods
We prospectively analyzed the data of patients with CLM who received percutaneous RFA. Dynamic contrast-enhanced computed tomography was used to assess ablation. All CLMs were divided into development and internal validation cohorts. We analyzed the predictive factors of iRFA in the development cohort and assessed the status of NIHM and OS of all patients through the Kaplan–Meier method.
Results
One hundred and sixty-four patients (mean age, 60.6 ± 11.3 years; 104 men) with 338 tumors were included in this study. Perivascular tumor location, tumor size ≥ 20 mm, and minimal ablative margin were independent predictors of iRFA. The area under the receiver operating characteristic curve was 0.884 and 0.857 for the development and internal validation cohorts, respectively. NIHM were more likely to occur in the iRFA group than in the complete RFA (cRFA) group (χ2 = 26.811, P < 0.001). The estimated median OS was 45 months, and the cumulative OS for 1, 3, and 5 years was 92.2%, 59.7%, and 41.2%, respectively. The OS of the iRFA group was 39 months shorter than that of the cRFA group (χ2 = 12.269, P < 0.001).
Conclusions
Non-perivascular tumor location, tumor size < 2 cm, and a sufficient minimum ablation margin are essential for cRFA. Incomplete RFAs are related to the occurrence of NIHM and a much shorter OS.