Abstract: Objective To analyze the efficacy and security of sintilimab combined with lenvatinib in the treatment of advanced hepatocellular carcinoma (HCC).Methods A total of 68 patients with advanced HCC were selected from January 2021 to December 2023 as the research subjects. Thirty-four patients in the control group received lenvatinib monotherapy, and 34 patients in the observation group received sintilimab combined with lenvatinib treatment. Patients' vital signs and clinical laboratory results were continuously evaluated until they died, lost contact, or the study was ended. The antitumour response was assessed using the HCC specific modified RECIST (mRECIST), the survival curves were plotted and the occurrence of adverse events during treatment was recorded.Results There were no significant differences in the baseline clinical data and the occurrence of adverse events during treatment between the two groups (P＞0.05). The median PFS were 11.5 months and 6.8 months in two groups, with significant difference (P=0.013, HR=0.568, 95%CI=0.359-0.886). The median OS were 21.5 months and 12.7 months in two groups, with significant difference (P=0.005, HR=0.426, 95%CI=0.237-0.782). After treatment, the ORR and DCR were 44.12% and 85.29%, respectively, in the observation group, and were 23.53% and 58.82% in the control group, with significant differences (P＜0.05).Conclusion Sintilimab combined with lenvatinib is effective and safe in the treatment of advanced HCC and may lead to a better long-term outcome than lenvatinib monotherapy.

Key words: Hepatocellular carcinoma, Sintilimab, Lenvatinib, Efficacy, Security