Notably, mainly consisting of its 3′-UTR truncations, PD-L1-involving abnormalities were prevalently found in EBV-positive T-cell and NK-cell proliferations (17–57%), including ENKTL (19 of 81 samples), aggressive NK-cell leukemia (ANKL, 4 of 7), and systemic EBV-positive T-cell lymphoproliferative disorder (EBV T-LPD, 1 of 6) (Fig. 1a, b). This evidence concerns the gene CD274 and aggressive NK-cell leukemia.