CD274 and neoplasm: Immunohistological quantification of PD-L1 using the combined positive score (PD-L1 positivity in tumor and tumor-infiltrating immune cells), showed a trend towards better engraftment for low combined positive score (CPS ≤ 10); whereas cases with high CPS were more likely to be rejected (CPS [yes] vs. CPS [no]: 18.22 vs. 33.41; Pearson r: -0.109] (Fig. 6A).