Combination of Radiotherapy and Atezolizumab plus Bevacizumab in Patients with Advanced Hepatocellular Carcinoma: A Pilot Study

Abstract

Following the results of the IMbrave150 study, Atezolizumab plus bevacizumab (Atezo/beva) became the first-line treatment in patients with advanced hepatocellular carcinoma (HCC). However, its real-world efficacy has been less satisfied. In this study, we investigated the efficacy of radiotherapy (RT) combined with Atezo/beva in patients with advanced HCC. Twenty patients received combination of RT and Atezo/beva between December 2021 and December 2022 at our institution. RT was administered in 10 fractions of 5 Gy between Atezo/beva cycles. Tumor response were evaluated on both imaging and tumor marker basis. The iRECIST guideline was used to assess treatment response after the combination treatment of RT and Atezo/beva. Primary endpoints were disease control rate (DCR) and overall response rate (ORR), and secondary endpoint was treatment related toxicity. All patients were BCLC C with advanced tumors associated with lymph node metastasis (7, 35%) or distant metastasis (8, 40%). Patients received RT between cycles of Atezo/beva, mostly (14, 70%) between 2nd and 3rd cycles. After a median follow-up of 3.2 months, DCR was 65% and ORR was 20%. Significant decrease in tumor marker of over 2-fold was shown in 10 patients (50%). Regarding treatment related toxicity, only 1 patient (5%) showed grade 3 neutropenic fever, and no grade 4 or 5 toxicity was seen. Combination of radiotherapy and Atezo/beva showed high response rate with tolerable treatment related toxicity in advanced HCC patients. Further prospective studies with larger patient cohort are warranted.