Supplementary Material for: Surgery Versus Radiofrequency Ablation for Small Hepatocellular Carcinoma: a Randomized Controlled Trial (SURF-Trial)

Introduction: It remains unclear which of surgery or radiofrequency ablation (RFA) is the more effective treatment for small hepatocellular carcinoma (HCC). We aimed to compare survival between patients undergoing surgery (surgery group) and patients undergoing RFA (RFA group). Methods: We conducted a randomized controlled trial involving 49 institutions in Japan. Patients with Child-Pugh scores ≤ 7, largest HCC diameter ≤ 3 cm, and ≤ 3 HCC nodules were considered eligible. The co-primary endpoints were recurrence-free survival (RFS) and overall survival (OS). The current study reports the final result of RFS, and the follow-up of OS is still ongoing. Results: During 2009–2015, 308 patients were registered. After excluding ineligible patients, the surgery and RFA groups included 150 and 151 patients, respectively. Baseline factors did not differ significantly between the groups. In both groups, 90% of patients had solitary HCC. The median largest HCC diameter was 1.8 cm (interquartile range, 1.5–2.2 cm) in the surgery group and 1.8 cm (interquartile range, 1.5–2.3 cm) in the RFA group. The median procedure duration (274 versus 40 minutes, P<0.01) and the median duration of hospital stay (17 days versus 10 days, P<0.01) were longer in the surgery group than in the RFA group. RFS did not differ significantly between the groups as the median RFS was 3.5 (95% confidence interval [CI], 2.6–5.1) years in the surgery group and 3.0 (95% CI, 2.4–5.6) years in the RFA group (hazard ratio, 0.92; 95% CI, 0.67–1.25; P=0.58). Discussion/Conclusion: Our study did not show which of surgery or RFA is the better treatment option for small HCC.