Comparative Effectiveness of Radiofrequency Ablation, Surgical Resection and Transplantation for Early Hepatocellular Carcinoma by Cancer Risk Groups: Results of Propensity Score-Weighted Analysis

Purpose: Controversies exist for which treatment is optimal for early hepatocellular carcinoma (HCC): radiofrequency ablation (RFA), surgical resection (SR), or transplantation (LT). We compared outcomes between treatments as first-line therapy for HCC patients measuring up to 5 cm or different cancer risk groups. Patients and methods: The Surveillance, Epidemiology, and End Results database was retrieved for HCC patients treated with RFA, SR, or LT between 2004 and 2015. The effects of three treatments were compared using propensity score, inverse probability of treatment weights adjustment, and instrumental variable analysis for overall survival (OS) and competing risks regression models for disease-specific survival (DSS). We also evaluated whether the effect of treatments varied according to baseline clinical characteristics by locally weighted regression method. Results: Of 7664 patients, RFA and SR yielded worse OS (HR 1.67, CI 1.43-1.70, P<0.001; HR 1.43, CI 1.40-1.67, P<0.001) and DSS (HR 2.00, CI 1.10-3.30, P<0.011; HR 2.50, CI 2.00-3.30, P<0.001) than LT. In patients with small tumors, SR may confer more survival benefits than RFA (HR>1) for different tumor sizes measuring up to 5 cm and may be an appropriate first-line treatment. Additionally, RFA has more survival benefits compared with SR (HR 0.83, CI 0.53-1.25) for those patients with low tumor risk and good general health condition (without any prognostic risk factors). However, those patients with a predicted 5-year overall mortality risk >30% seem to benefit more for SR than RFA. Conclusion: Due to a shortage of donors, RFA and SR can be applied as either primary management of HCC or as a bridging therapy for LT. Furthermore, SR is an effective option for patients with different HCC tumor size. However, RFA could achieve comparable survival benefits with SR for patients without any risk factors.