Factors Associated with Tumor Progression After Percutaneous Ablation of Hepatocellular Carcinoma: Comparison Between Monopolar Radiofrequency and Microwaves. Results of a Propensity Score Matching Analysis.

To identify risk factors for local and distant intrahepatic tumor progression after percutaneous ablation of HCC and to compare MWA with monopolar RFA. Consecutive patients with early or very early HCC who underwent percutaneous monopolar RFA or MWA were included. Factors associated with local and distant tumor progression were identified. Propensity score matching (PSM) was used to limit bias. Statistical analyses were performed with the Kaplan-Meier method using the log-rank test and Cox regression models. One hundred ninety HCC (mean diameter 23 ± 8.6 mm) were treated by RFA (n = 90, 47%) or MWA (n = 100, 53%) in 152 patients (mean age 63 ± 11, 79% men) between 2009 and 2016. The technical success rate was 97.4% (n = 185 HCC). After a median follow-up of 24.6 months (IQR: 9.7-37.2), 43 (23%), HCC showed local tumor progression [after a median of 13.4 months (IQR: 5.8-24.3)] and 91 (63%) patients had distant intrahepatic tumor progression (after a median of 10.4 months (IQR: 5.7-22). The cox model after PSM identified treatment by RFA (HR, 2.89; P = 0.005), HCC size ≥ 30 mm (HR, 3.12; P = 0.007) and vascular contact (HR, 3.43; P = 0.005) as risk factors for local progression. Factors associated with distant intrahepatic progression were HCC ≥ 30 mm (HR, 1.94; P = 0.013), serum AFP > 100 ng/mL (HR, 2.56; p = 0.002), and hepatitis B carrier (HR, 0.51; p = 0.047). The rate of local HCC progression was lower after MWA than monopolar RFA, regardless of tumor size and vascular contact. The ablation technique did not influence the risk of distant intrahepatic tumor progression.