CD274 and neoplasm: A possible explanation for these conflicting findings is that the predictive values of tumour and TII PD-L1 expression depends on the drug target; the response to nivolumab (an anti-PD-1 antibody) appears to correlate with PD-L1 expression on tumour cells but not TIIs, while the response to atezolizumab and avelumab (anti-PD-L1 antibodies) correlates with PD-L1 expression on TIIs.