PDCD1 and neoplasm: We found that the expression of PD‐1, PD‐L1, CTLA‐4, LAG‐3, TIM‐3, and TIGIT in tumor samples was significantly higher than those in normal samples (all p < .001) and the expression of PD‐1, PD‐L1, and CTLA‐4, LAG‐3, and TIGIT in Cluster 2 was significantly higher than those in Cluster 1 (Figure 4A–F).