CD274 and neoplasm: In summary, although we show no definite association between the changes in PD-L1 or PD-L2 expression (tumor and immune cells), TIL densities, and HLA-class I expression between pre-(C) RT tissue and the local recurrence sites after (C)RT, there was a positive association between the upregulation of PD-L1 expression on tumor cells and an increased CD8+TIL density.