CD274 and neoplasm: In conclusion, we found PD-L1 expression concordance between primary and paired metastatic tumor in 88% and 90.7% of cases using 1% and 50% cutoff, respectively; regarding local tumor recurrences, a lower concordance (66%) at 1% cutoff was detected, suggesting the possible need for tumor re-biopsy in the setting of second line pembrolizumab treatment.