PDCD1 and neoplasm: Upon stratification by median values, the clinical feature analysis showed that the expression level of PD-1 in CD8+ TILs was correlated with lymph node spread (P=0.03) and tumor infiltration depth (P=0.002), while 4-1BB expression was related to surgical status (P=0.003) and FIGO stage (P=0.041) (Supplementary Table 1).