Percutaneous cryoablation of subcapsular hepatocellular carcinoma: a retrospective study of 57 cases.

PURPOSE This study aims to evaluate the safety and effectiveness of the percutaneous cryoablation for subcapsular hepatocellular carcinoma (HCC). METHODS A total of 57 patients with subcapsular (<1 cm form the liver edge) HCCs (68 lesions), who were treated with CT-guided percutaneous cryoablation in the Department of Interventional Radiology of our hospital between July 1, 2016 and September 1, 2018, were retrospectively included. Complete ablation rate, local tumor progression (LTP) and treatment-related complications were evaluated. Furthermore, the degree of intraoperative and postoperative pain was measured with the visual analog scale (VAS), and laboratory findings were compared before and after the procedure. RESULTS All patients successfully completed the treatment. The mean follow-up period was 12.8 months (range, 3-27 months), and the complete ablation rate was 97% (66/68). Local tumor progression occurred in 11 lesions (16.2%), and the 6-, 12- and 18-month cumulative LTP rates were 4.0%, 8.2% and 20.5%, respectively. Two patients (3.5%, 2/57) developed major complications, and 12 patients had minor complications (22.8%, 12/57). The mean VAS score during the operation was 1.65 points (range, 1-3 points). Postoperative pain worsened in 3 patients, and the VAS scores reached 4-5. Transient changes in biochemical and hematologic markers were observed. CONCLUSION Percutaneous cryoablation for subcapsular HCC is safe and effective, the procedure is simple and the patients suffer less pain.