CD274 and neoplasm: However, a difference in PD‐L1 TPS scores of up to 55% between different tumor sites in the same patient was observed, consistent with previous reports of PD‐L1 heterogeneity in lung26 and other cancers.27 This means that with a cut‐off of ≥50% PD‐L1 TPS for positivity (the cut‐off for the companion diagnostic PD‐L1 assay for pembrolizumab), 20%‐60% of individuals in this study would have a different final PD‐L1 result if different tumor sites were tested.