There were more immune components in the high immune cell infiltration cluster than in the low immune cell infiltration cluster, but the tumor purity of the high immune cell infiltration cluster was lower, and the expression levels of TIGIT, PDCD1, LAG3, HAVCR2, CTLA4 and the HLA family were also higher in the high immune cell infiltration cluster (Figures 1C, D). Here, PDCD1 is linked to neoplasm.