Supplementary Material for: Treatment of Intermediate-Stage Hepatocellular Carcinoma in Japan: Position of Curative Therapies

Background: Transcatheter arterial chemoembolization (TACE) is the standard therapy for intermediate-stage (IM) hepatocellular carcinoma (HCC). However, IM-HCC includes various clinical conditions, and various therapies were conducted in practice. In this study, we retrospectively analyzed the actually conducted treatments for IM-HCC and their efficacies to elucidate the treatment strategies suitable for IM-HCC. Methods: This study included 627 IM-HCC of 5,260 HCC from 9 hospitals. We examined the treatment strategies of these patients and analyzed the efficacy of each therapy with the Cox proportional hazard model and propensity score-matched analysis. Results: Liver resection, radiofrequency ablation (RFA), and TACE were performed in 165, 108, and 351 patients, respectively. Liver resection and RFA were preferably selected in cases of Barcelona Clinic Liver Cancer (BCLC)-B1/B2, and patient survival was significantly longer than in those treated with TACE (p< 0.0001). However, no beneficial effect of these active therapies was observed in cases of BCLC-B3/B4. Multivariate analysis revealed that surgical resection (hazard ratio = 0.384) and RFA (hazard ratio = 0.597) were negative risk factors for survival. Propensity score-matching analysis revealed that ­survival of RFA-treated patients was longer than that of TACE-treated patients (p = 0.036). Conclusion: RFA and surgical resection were effective for IM-HCC, particularly in BCLC-B1/B2 cases.