Radiofrequency ablation of unresectable liver tumors: factors associated with incomplete ablation or local recurrence

BACKGROUND: Radiofrequency ablation (RFA) of liver tumors is associated with a risk of incomplete ablation or local recurrence. METHODS: One hundred sixty-eight patients with 311 unresectable liver tumors were included. Effects of different variables on incomplete ablation and local recurrence were analyzed. RESULTS: There were 132 hepatocellular carcinomas and 179 liver metastases. Tumor size was 24 (+/- 13) mm. Two hundred twenty-six tumors were treated percutaneously, and 85 through open approach (associated with liver resection in 42 cases). There was no mortality. Major morbidity rate was 7%. Incomplete ablation and local recurrence rates were 14% and 18.6%. Follow-up was 29 months. On multivariate analysis, factors associated with incomplete ablation were tumor size (>30 mm vs <= 30 mm, P = .004) and approach (percutaneous vs open, P = .0001). Factors associated with local recurrence were tumor size (>30 rum vs <= 30 mm, P = .02) and patient age (>65 years vs <= 65 years, P = .05). CONCLUSIONS: RFA is effective to treat unresectable liver tumors. However, there is a risk of incomplete ablation when percutaneously treating tumors >30 mm. When tumor ablation is completely achieved, the main factor associated with local recurrence is tumor size >30 mm. (C) 2010 Elsevier Inc. All rights reserved.