Radioembolization Is a Safe and Effective Treatment for Hepatocellular Carcinoma with Portal Vein Thrombosis: A Propensity Score Analysis

Background/Aims: Limited treatment options are available for patients with hepatocellular carcinoma (HCC) with portal vein thrombosis (PVT). Transarterial radioembolization using Yttrium-90 microspheres is a new treatment modality for HCC with PVT. For this analysis, we compared responses to treatment with radioembolization and with sorafenib. Methods: We evaluated 32 patients who were part of a multicenter retrospective cohort. All patients had PVT without extrahepatic metastasis and were treated with radioembolization in one of six tertiary referral hospitals in Korea. We retrospectively enrolled another 31 consecutive PVT patients without extrahepatic metastasis from a single center who received sorafenib treatment to serve as the control group. We used inverse probability weighting (IPW) using propensity scores to adjust for the between-group differences in baseline characteristics. Results: At 3 months, the response rate and disease control rate were 32.1% (9/32) and 57.1% (16/32), respectively, in the radioembolization group and 3.2% (1/31) and 41.9% (13/31) in the sorafenib group. Median overall survival (OS) and time to progression (TTP) were not significantly different between the radioembolization group and the sorafenib group (13.8 months and 10.0 months, P = 0.22; and 6.0 months and 6.0 months, P = 0.08; respectively). No differences in OS (P = 0.97) or TTP (P = 0.34) were observed after IPW was applied to balance the population characteristics. The sorafenib group showed significantly more grade 3/4 adverse effects than the radioembolization group (P