The impact of PD-1 inhibitors on prognosis in unresectable hepatocellular carcinoma treated with TACE and lenvatinib: a retrospective study

Abstract Our aim was to explore whether programmed death receptor-1 (PD-1) inhibitors would improve the prognosis of unresectable hepatocellular carcinoma (HCC) treated with transarterial chemoembolization (TACE) plus lenvatinib. In this single-center retrospective study, patients with unresectable HCC who underwent TACE and were administered lenvatinib with or without PD-1 inhibitors were enrolled and divided into the TACE + lenvatinib group and TACE + lenvatinib + PD-1 group. Overall survival (OS), progression-free survival (PFS) and tumor response were assessed by the Response Evaluation Criteria in Solid Tumors (RECIST v1.1 and mRECIST). Treatment-related adverse events (AEs) were evaluated according to the Common Terminology Criteria for Adverse Events (CTCAE, version 5.0). In total, 35 eligible patients with unresectable HCC were included; 82.9% of patients had Hepatitis B virus (HBV) infection, and 88.6% of patients had liver cirrhosis. A total of 88.6% of patients had multiple tumors, and the median diameter of the largest tumor was 10.1 cm. A total of 14.3% of patients had extrahepatic metastasis, and 51.4% of patients had portal vein tumor thrombus. The percentages of BCLC stages A, B and C were 5.7%, 28.6% and 65.7%, respectively. There were 16 patients in the TACE + lenvatinib group and 19 patients in the TACE + lenvatinib + PD-1 group. The median follow-up time was 7.7 months (ranging from 1.7 to 31.6 months). Neither group reached the median overall survival. Under RECIST v1.1 criteria, the median PFS was 10.4 and 7.9 months in the TACE + lenvatinib and TACE + lenvatinib + PD-1 groups (HR, 1.13; 95% CI 0.45–2.84; p = 0.80), the objective response rates (ORR) were 31.3% and 31.6% (p > 0.05), and the disease control rates (DCR) were 93.8% and 78.9% (p > 0.05), respectively. Under mRECIST criteria, the median PFS was 10.4 and 10.1 months (HR, 0.98; 95% CI 0.38–2.54, p = 0.97), the ORR was 62.5% and 63.2% (p > 0.05), and the DCR was 93.8% and 73.7% (p > 0.05), respectively. Overall, AEs were relatively similar between the two groups. PD-1 inhibitors did not improve the PFS and tumor response of unresectable HCC treated with TACE plus lenvatinib. Hepatitis B infection, liver cirrhosis, portal vein tumor thrombus, multiple tumors and large tumor diameter may be potential factors that affect the efficacy of PD-1 inhibitors but need further validation.