A previous study92 revealed that tumor cells can produce abnormally spliced PD-L1 that lacks the transmembrane domain, which is secreted extracellularly and displays high affinity for anti-PD-L1 antibodies, indicating that tumor-derived PD-L1 is not constant and may undergo changes during packing into EVs or at certain biological stages; this finding warrants further research on the increased affinity of PD-L1 for anti-PD-L1 antibodies. This evidence concerns the gene CD274 and neoplasm.