Clinical characteristics of patients with advanced hepatocellular carcinoma who received long-term treatment with atezolizumab and bevacizumab for more than one year.

Abstract

532 Background: Atezolizumab plus bevacizumab (Ate/Bev) has become the standard of care since 2020 as a first-line systemic therapy for unresectable hepatocellular carcinoma (HCC). However, studies on patients receiving long-term treatment with Ate/Bev are still lacking. In this study, we evaluated the clinical characteristics and impacts on patients receiving Ate/Bev treatment for more than one year. Methods: We prospectively enrolled 246 patients with unresectable HCC who received Ate/Bev treatment at three tertiary cancer centers in Korea between May 2020 and April 2022. Comparative analyses were performed between patients treated with Ate/Bev for more than one year and those treated for less than one year. Additionally, treatment-related adverse events (AEs), and changes in liver function were evaluated. Results: Of the 246 patients, 69 (28.0%) were treated with Ate/Bev for more than one year. The long-term treatment group showed better Eastern Cooperative Oncology Group performance status, liver function, and lower residual hepatic tumor burden at baseline, compared to the group treated for less than one year. Furthermore, the long-term treatment group had a higher incidence of atezolizumab-related thyroid dysfunction (30.4% vs. 10.7%, p ‹ 0.001), dermatologic toxicity (30.4% vs. 14.1%, p = 0.006), and bevacizumab-related hypertension (43.5% vs. 22.6%, p = 0.002) and proteinuria (68.1% vs. 39.0%, p ‹ 0.001), compared to the less than one-year treatment group. The median time to onset of thyroid dysfunction and dermatologic toxicity after Ate/Bev treatment was 2.8 months and 3.3 months, respectively, while the median time to onset of hypertension and proteinuria was 4.2 months and 6.8 months, respectively. In the long-term treatment group, 30 patients (43.5%) showed an increase in Child-Pugh score, 20 (29.0%) had an increase in Child-Pugh grade during Ate/Bev treatment. Conclusions: The Ate/Bev long-term treatment group had better performance status, liver function, and a lower residual hepatic tumor burden at baseline. Atezolizumab-related immunologic adverse events occurred mostly early in the course of treatment, whereas bevacizumab-related adverse events occurred relatively later. In addition, a fraction of patients experienced deterioration of liver function during long-term Ate/Bev treatment.