Some experiments showed that in HNSCC, the scores of IPS with CTLA4 blocker, IPS with CTLA4, and PD1/PDL1/PdL2 blocker in the low-risk group were significantly higher than those in the high-risk group, which was consistent with our experimental results [100]. Here, PDCD1LG2 is linked to head and neck squamous cell carcinoma.