CD274 and neoplasm: The study provides preliminary data to support that PD‐L1 is evaluable on HNC and NSCLC CTCs, consistent with a number of recent studies.5, 6, 29, 45 CTCs have been shown to have a higher PD‐L1 positivity compared to tumor tissue.46 In this study, the patient CTC PD‐L1 expression levels were found to be comparable to known cell lines.