Clinical Investigation Evaluating Safety and Efficacy of Selective Intra-arterial 166Holmium Radiation Therapy in Combination With Atezolizumab and Bevacizumab for Non Resectable Hepatocellular Carcinoma

Brief Summary

The goal of this clinical trial is to evaluate the added value of 166Holmium SIRT to Atezolizumab-Bevacizumab in patients with non resectable HCC. The primary endpoint is the Best Objective Response Rate at 6 months after 166Holmium SIRT according to mRECIST. Participants will be treated by : * Approved first line systemic therapy: Atezolizumab (1200mg Q3W, IV) with Bevacizumab (15mg/kg Q3W, IV) * In combination with 166Holmium selective internal intra-arterial radiation therapy (Quirem Spheres®, the investigational medical device) after a work-up phase considered as "favorable". Participants will be followed up to 12 months after the first cycle of Atezolizumab and Bevacizumab therapy.