Treatment of Focal Liver Tumors with Percutaneous Radio-frequency Ablation: Complications Encountered in a Multicenter Study

PURPOSE: To report complications encountered by members of a collaborative group who performed radio-frequency (RF) ablation in patients with focal liver cancer. MATERIALS AND METHODS: Members of 41 Italian centers that were part of a collaborative group used a percutaneous internally cooled RF ablation technique and a standardized protocol for follow-up. They completed a questionnaire regarding number of deaths, presumed cause of death, and likelihood of its relationship to the RF procedure; number and types of major complications; and types of minor complications and side effects. Enrollment included 2,320 patients with 3,554 lesions (size, 3.1 cm +/- 1.1 SD in diameter): 1,610 had hepatocellular carcinoma with chronic liver disease; 693 had metastases, predominantly from colorectal cancer (n = 501); and 17 had cholangiocellular carcinoma. Number and characteristics of complications (ie, deaths and major and minor complications) attributed to the procedure were reported. Data were subsequently analyzed with analysis of variance to determine whether the major complication rate was related to tumor size, number of ablation sessions, or electrode type (single or cluster). RESULTS: In total, 3,554 lesions were treated. Six deaths (0.3%) were noted, including two caused by multiorgan failure following intestinal perforation; one case each of septic shock following Staphylococcus aureus-caused peritonitis, massive hemorrhage following tumor rupture, liver failure following stenosis of right bile duct; and one case of sudden death of unknown cause 3 days after the procedure. Fifty (2.2%) patients had additional major complications. The most frequent of these were peritoneal hemorrhage, neoplastic seeding, intrahepatic abscesses, and intestinal perforation. An increased number of RF sessions were related to a higher rate of major complications (P <.01), whereas the number of complications was not significantly different when tumor size or electrode type were compared. Minor complications were observed in less than 5% of patients. CONCLUSION: Results of this study confirm that RF ablation is a relatively low-risk procedure for the treatment of focal liver tumors.