Efficacy and Safety of Percutaneous Argon-Helium Cryoablation for Hepatocellular Carcinoma Abutting the Diaphragm

Purpose: To evaluate the efficacy and safety of percutaneous argon-helium cryoablation (CA) for hepatocellular carcinoma (HCC) abutting the diaphragm (<5 mm). Materials and Methods: A total of 61 consecutive patients (50 men, 11 women; mean age, 56.3 +/- 12.1 years old; range, 32-83 years) with 74 HCC tumors (mean size, 3.3 +/- 1.7 cm; range, 0.8-7 cm) who were treated with percutaneous argon-helium CA were enrolled in this retrospective study. Adverse events were evaluated according to Common Terminology Criteria for Adverse Events, version 5.0. Local tumor progression (LTP) and overall survival (OS) were analyzed using the Kaplan-Meier method and the log-rank test, The risk factors associated with OS and LTP were evaluated using univariate and multivariate Cox regression analysis. Results: No periprocedural (30-day) deaths occurred. A total of 29 intrathoracic adverse events occurred in 24 of the 61 patients. Major adverse events were reported in 5 patients (pleural effusion requiring catheter drainage in 4 patients and pneumothorax requiring catheter placement in 1 patient). Median follow-up was 18.7 months (range, 2.3-60.0 months). Median time to LTP after CA was 20.9 months (interquartile range [IQR], 14.1-30.6 months). Median times of OS after CA and diagnosis were 27.3 months (IQR, 15.1-45.1 months) and 40.9 months (interquartile range, 24.8-68.6 months), respectively. Independent prognostic factors for OS included tumor location (left lobe vs right lobe; hazard ratio [HR], 2.031; 95% confidence interval [CI], 1.062-3.885; P = .032) and number of intrahepatic tumors (solitary vs multifocal; HR, 2.684; 95% CI, 1.322-5.447; P = .006). Independent prognostic factors for LTP included age (HR, 0.931; 95% CI, 0.900-0.963; P < .001), guidance modality (ultrasound vs computed tomography and US; HR, 6.156 95% CI, 1.862-20.348; P = .003) and origin of liver disease. Conclusions: Percutaneous argon-helium CA is safe for the treatment of HCC abutting the diaphragm, with acceptable LTP and OS.