In agreement with Li et al. [39], we conclude that circulating PD-L1+ MVs in patients classified as PD-L1− by IHC indicate the presence of PD-L1+ TCs at tumour sites not explored by IHC testing, highlighting that PD-L1 scoring by IHC is biased by heterogeneous PD-L1 expression in the tumour. The gene discussed is CD274; the disease is neoplasm.