A Real-World Comparative Analysis of Atezolizumab Plus Bevacizumab and Transarterial Chemoembolization Plus Radiotherapy in Hepatocellular Carcinoma Patients with Portal Vein Tumor Thrombosis

SIMPLE SUMMARY: This multicenter cohort study is the first to compare the clinical outcomes between the Atezolizumab-plus-bevacizumab (Ate/Bev) and transarterial-chemoembolization-plus-radiotherapy (TACE + RT) therapies in hepatocellular carcinoma (HCC) patients with portal vein tumor thrombosis (PVTT) who had no metastasis. Through detailed analyses, our study revealed that the Ate/Bev treatment provided superior one-year survival compared to the TACE + RT treatment. The superior outcome of the Ate/Bev therapy was constantly observed in patients with an extensive HCC burden. Meanwhile, patients with unilobar disease demonstrated comparable outcomes between the two treatment groups. Finally, in the propensity score-matching analysis, both one-year survival and progression-free survival rates were higher in the Ate/Bev treatment group. These results suggest that Ate/Bev treatment should be considered as the primary treatment option for HCC patients with PVTT. With respect to TACE + RT, this could also be considered as an alternative treatment option alongside Ate/Bev therapy in patients with unilobar intrahepatic HCC. ABSTRACT: This study aimed to compare the treatment outcomes of atezolizumab-plus-bevacizumab (Ate/Bev) therapy with those of transarterial chemoembolization plus radiotherapy (TACE + RT) in hepatocellular carcinoma (HCC) patients with portal vein tumor thrombosis (PVTT) and without metastasis. Between June 2016 and October 2022, we consecutively enrolled 855 HCC patients with PVTT. After excluding 758 patients, 97 patients (n = 37 in the Ate/Bev group; n = 60 in the TACE + RT group) were analyzed. The two groups showed no significant differences in baseline characteristics and had similar objective response and disease control rates. However, the Ate/Bev group showed a significantly higher one-year survival rate (p = 0.041) compared to the TACE + RT group, which was constantly displayed in patients with extensive HCC burden. Meanwhile, the clinical outcomes were comparable between the two groups in patients with unilobar intrahepatic HCC. In Cox-regression analysis, Ate/Bev treatment emerged as a significant factor for better one-year survival (p = 0.049). Finally, in propensity-score matching, the Ate/Bev group demonstrated a better one-year survival (p = 0.02) and PFS (p = 0.01) than the TACE + RT group. In conclusion, Ate/Bev treatment demonstrated superior clinical outcomes compared to TACE + RT treatment in HCC patients with PVTT. Meanwhile, in patients with unilobar intrahepatic HCC, TACE + RT could also be considered as an alternative treatment option alongside Ate/Bev therapy.