Brachytherapy with Iodine-125 seeds for treatment of portal vein-branch tumor thrombus in patients with hepatocellular carcinoma

BACKGROUND: There is currently no widely-accepted consensus for the management of hepatocellular carcinoma with portal vein tumor thrombus. We evaluate the safety and efficacy of ultrasound-guided percutaneous brachytherapy with iodine-125 seeds for the treatment of hepatocellular carcinoma with portal vein-branch tumor thrombus (PVBTT). METHODS: Sixty-nine hepatocellular carcinoma patients with PVBTT were enrolled; 34 received transarterial chemoembolization (TACE) combined with iodine-125 seeds implanted in the PVBTT; 35 were treated with TACE alone. Adverse events, objective response rate, disease control rate, progression-free survival, and overall survival were compared between the two groups. Tumor responses of PVBTT and intrahepatic tumor were correlated. Multivariate and subgroup analyses were conducted for overall survival. RESULTS: No grade 3 or 4 adverse events were recorded, and there was no difference in grade 1 or 2 adverse events between the two groups. Objective response rate and disease control rate for PVBTT were 58.9 and 91.2%, respectively, in the combined treatment group, which were significantly greater than the 5.7 and 54.3% rates, respectively, in the TACE-alone group (both p’s ≤ 0.001). Intrahepatic tumor response was positively correlated with the PVBTT response (γ = 0.782, p < 0.01). Survival outcomes were better in the combined treatment group than in the TACE-alone group: the median progression-free survival for PVBTT was 9 months versus 3 months (HR = 0.187 [95% CI: 0.101, 0.345], p < 0.001), and the median overall survival was 11 months versus 7 months (HR = 0.448 [95% CI: 0.265, 0.758], p = 0.003). Multivariate analysis revealed that application of brachytherapy and lower grade PVBTT (Vp1 + Vp2 vs. Vp3) were protective predictors of overall survival. In stratified analysis, the benefit of overall survival was more significant in the subgroup of PVBTT Vp1 + Vp2 rather than in Vp3. CONCLUSIONS: The combination of iodine-125 seed brachytherapy guided by ultrasound and TACE is a convenient, safe, and effective treatment for patients with HCC and PVBTT, conferring a better survival benefit than TACE alone. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12885-021-08680-0.