Objective Response and Progression-Free Survival Contribute to Prolong Overall Survival in Atezolizumab plus Bevacizumab Treatment for Unresectable Hepatocellular Carcinoma

Abstract

<b><i>Introduction:</i></b> Atezolizumab plus bevacizumab (Atez/Bev) is a standard treatment for unresectable hepatocellular carcinoma (HCC) due to its good antitumor and survival prolongation effects. Post-progression survival (PPS) has been reported to be a great contributor in the treatment with tyrosine kinase inhibitors for unresectable HCC. This study aimed to clarify the significance of progression-free survival (PFS) or PPS of Atez/Bev treatment for HCC. <b><i>Methods:</i></b> We analyzed the correlations of PFS and PPS with overall survival (OS) in studies of HCC patients treated with Atez/Bev and evaluated the contribution to OS in Atez/Bev treatment with patients at our institutions as clinical practice. <b><i>Results:</i></b> Analysis of 18 studies involving 3,752 patients treated with Atez/Bev found that PPS had a stronger correlation with OS (<i>R</i>² = 0.872, <i>p</i> &lt; 0.001) than did PFS (<i>R</i>² = 0.605, <i>p</i> = 0.001). Analysis of 80 patients with unresectable HCC treated with Atez/Bev found that presence of antitumor responses during Atez/Bev was the most significant contributor to OS, and post-progression treatment after Atez/Bev also significantly contribute to OS. <b><i>Conclusion:</i></b> The presence of antitumor response with tumor shrinkage during Atez/Bev treatment contributes to good OS through its durable response. Atez/Bev treatment could be considered as first-line treatment for unresectable HCC. However, there is a need for optimal biomarkers for good antitumor response.