CD4 and neoplasm: Tumours harbouring PD-L1+ TILs were also the ones displaying higher CD4+/FOXP3+ (49.0 vs. 8.2 cells/mm2, p = 0.002) and CD8+/PD-1+ TIL cell density (40.8 vs. 12.3 cells/mm2, p = 0.016, Fig. 3D and E).