CD274 and nasopharyngeal carcinoma: When the median value was used as a cutoff, no significant association was found between the infiltration densities of PDL1+ TCs, PDL1+ TILs, or any PDL1+ TILs subpopulations and the clinicopathological characteristics (Supplementary Table 4), implying that the higher infiltration density of PDL1+ Tregs and PDL1+ Teffs in the unfavorable group was independent of other prognostic factors for NPC.