Aim: To determine if PD-L1 can be used as a biomarker to predict the efficacy of anti-PD-1/PD-L1 inhibitors in hepatocellular carcinoma (HCC). Methods: Relevant studies from a specific search of the four databases from October 2014 to December 2022 were included in this meta-analysis. Results: Higher PD-L1 expression levels were associated with a higher objective response rate (ORR). Higher PD-L1 expression levels on tumor cells and tumor proportion score were associated with higher ORR. PD-L1 was capable of predicting the effectiveness of nivolumab. Dako 28-8 is a promising assay for HCC. Conclusion: PD-L1 is a predictive biomarker for ORR in HCC. Tumor proportion score and PD-L1 expression levels on tumor cells are potential scoring algorithms.
Trial registration: ClinicalTrials.gov NCT01658878 NCT02576509 NCT03463876 NCT02658019 NCT02989922 NCT02702414.
Keywords: PD-L1; biomarker; hepatocellular carcinoma; meta-analysis; systematic review.
Clinically, liver cancer patients with high PD-L1 levels may not benefit from immunotherapy. Conversely, some patients with low PD-L1 level can benefit from it. Therefore, the concept of PD-L1 as a predictive indicator in liver cancer is defective. Whether PD-L1 can serve as an indicator in liver cancer patients receiving immunotherapy needs urgent confirmation. In this work, we evaluated the feasibility of PD-L1 as a prognostic biomarker for immunotherapy. The results suggested that high expression of PD-L1 by tumor cells rather than tumor tissue was correlated with better prognosis.