The potential efficacy of atezolizumab plus bevacizumab treatment for hepatocellular carcinoma patients with macroscopic portal vein tumor thrombus.

Purpose: The prognosis of patients with hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT) in the first-order or main trunk/contralateral branches (Vp3/4) is poor. The present study aimed to clarify the real-world data of atezolizumab plus bevacizumab treatment (Ate/bev) for HCC patients with Vp3/4 PVTT.

Methods: The subjects of this study were 22 consecutive HCC patients with Vp3/4 PVTT, who were treated with Ate/bev. Survival rates and radiological responses were evaluated based on the modified albumin-bilirubin (mALBI) grade [mALBI 1 + 2a (1/2a) versus 2b + 3 (2b/3)] using the modified Response Evaluation Criteria in Solid Tumors.

Results: The median survival time of the 22 patients was 15.0 months, with 1- and 2-year survival rates of 62.7% and 49.3%, respectively. The objective response (OR) rates of patients with mALBI 1/2a and 2b/3 were 91.7% (11/12) and 10.0% (1/10), respectively, with a significant difference (p < 0.001). The 2-year survival rates of patients with mALBI 1/2a and 2b/3 were 78.6% and 20.0%, respectively, with a significant difference (p = 0.0041).

Conclusion: Ate/bev was effective for treating HCC patients with Vp3/4 PVTT. OR rate and MST were favorable, particularly for patients with preserved liver function (mALBI 1/2a), suggesting its great potential for the treatment of HCC in patients with Vp3/4 PVTT.