CD274 and neoplasm: Median densities for both PD-L1+ and PD-L1− macrophages were higher in tumour stromal (110/mm2 for PD-L1+ and 991/mm2 for PD-L1−) than intraepithelial regions (11.5/mm2 for PD-L1+ and 119/mm2 for PD-L1−).