Characterization of genomic alterations, tumor mutational burden and PDL1 expression in 181 Chinese hepatocellular carcinomas

e24276Background: Hepatocellular carcinoma (HCC), the most common hepatic malignancy, is the second leading cause of cancer-related death worldwide. China accounts for more than 50% of new HCC cases and deaths in the world. The genomic profiles of HCC in Chinese patients had not been thoroughly elucidated to facilitate diagnosis and treatment. Methods: FFPE tumor and matched blood samples of 181 Chinese HCC patients, including 152 males (median age of 54) and 29 females (median age of 52), were collected for next-generation sequencing-based 450 genes panel assay. Genomic alterations (including single base substitutions, short and long insertions/deletions, copy number variations, and gene rearrangement in selected genes) and tumor mutational burden were assessed. In addition, the expression of tumor cell PDL1 was also evaluated by FDA-cleared DAKO 22c3 antibody. Results: The most frequently mutated genes in 181 Chinese HCC were TP53 (59.7%), TERT (34.3%), CTNNB1 (21.5%), AXIN1 (12.2%), RB1 (11.0%), STK24 ...