Risk of tumour progression in early-stage hepatocellular carcinoma after radiofrequency ablation

Background: This study aimed objectively to quantify the risk of turnout progression beyond the Milan criteria following radiofrequency (RF) ablation for hepatocellular carcinoma (HCC) and to identify factors associated with tumour progression. Methods: Some 111 patients (136 tumours) with liver cirrhosis undergoing RF ablation for HCC within Milan criteria between February 2004 and June 2007 were enrolled in the study. Data were analysed retrospectively from a prospectively collected database. Results: The cumulative probability of tumour progression beyond the Milan criteria at 6, 12, 18, 24 and 36 months of RF ablation was 6.4, 11.0, 16.1, 21.2 and 44.8 per cent respectively. On multivariable analysis, factors independently associated with tumour progression were failure to achieve primary technique effectiveness (P = 0.005), alpha-fetoprotein level above 200 ng/ml (P = 0.013) and Child-Pugh grade B cirrhosis (P = 0.034). Failure to achieve primary RF ablation technique effectiveness was associated with tumour location in segment VIII (P = 0.033), a cool-down temperature of 70 degrees C or less (P = 0.043) and multiple overlapping ablations (P = 0.029). Conclusion: This study provides clinicians with an objective risk of tumour progression beyond the Milan criteria after RF ablation at multiple time points. Primary technique failure is identified as a risk factor for tumour progression.