Extracellular vesicles carrying PD‐L1 might be useful as diagnostic and prognostic markers, for example in pancreatic cancer [137], and as indicators of treatment response as reported in the context of head and neck squamous cell carcinoma [135], non‐small‐cell lung cancer [149], and melanoma [133, 149]. This evidence concerns the gene CD274 and head and neck squamous cell carcinoma.