[HTML][HTML] Comparative study of the PD-L1 status between surgically resected specimens and matched biopsies of NSCLC patients reveal major discordances: a …
M Ilie, E Long-Mira, C Bence, C Butori, S Lassalle… - Annals of …, 2016 - Elsevier
M Ilie, E Long-Mira, C Bence, C Butori, S Lassalle, L Bouhlel, L Fazzalari, K Zahaf, S Lalvée…
Annals of Oncology, 2016•ElsevierBackground High expression of programmed death ligand-1 (PD-L1) on tumor cells (TC)
and/or on tumor-infiltrating immune cells (IC) is associated with a high response rate in
patients with advanced nonsmall-cell lung cancer (NSCLC) treated with PD-L1 inhibitors.
The use of a PD-L1 immunohistochemical (IHC) test in determining the responsiveness to
immunotherapy has raised the question of the reliability and reproducibility of its evaluation
in lung biopsies compared with corresponding resected surgical specimens. Patients and …
and/or on tumor-infiltrating immune cells (IC) is associated with a high response rate in
patients with advanced nonsmall-cell lung cancer (NSCLC) treated with PD-L1 inhibitors.
The use of a PD-L1 immunohistochemical (IHC) test in determining the responsiveness to
immunotherapy has raised the question of the reliability and reproducibility of its evaluation
in lung biopsies compared with corresponding resected surgical specimens. Patients and …
Background
High expression of programmed death ligand-1 (PD-L1) on tumor cells (TC) and/or on tumor-infiltrating immune cells (IC) is associated with a high response rate in patients with advanced nonsmall-cell lung cancer (NSCLC) treated with PD-L1 inhibitors. The use of a PD-L1 immunohistochemical (IHC) test in determining the responsiveness to immunotherapy has raised the question of the reliability and reproducibility of its evaluation in lung biopsies compared with corresponding resected surgical specimens.
Patients and methods
PD-L1 expression in TC and IC was assessed in 160 patients with operable NSCLC on both whole surgical tissue sections and matched lung biopsies, by using a highly sensitive SP142 IHC assay. The specimens were scored as TC 0–3 and IC 0–3 based on increasing PD-L1 expression.
Results
PD-L1 expression was frequently discordant between surgical resected and matched biopsy specimens (the overall discordance rate = 48%; 95% confidence interval 4.64–13.24) and κ value was equal to 0.218 (poor agreement). In all cases, the biopsy specimens underestimated the PD-L1 status observed on the whole tissue sample. PD-L1-positive IC tumors were more common than PD-L1-positive TC tumors on resected specimens. The discrepancies were mainly related to the lack of a PD-L1-positive IC component in matched biopsies.
Conclusions
Our results indicate relatively poor association of the PD-L1 expression in TC and IC between lung biopsies and corresponding resected tumors. Although these results need to be further validated in larger cohorts, they indicate that the daily routine evaluation of the PD-L1 expression in diagnostic biopsies can be misleading in defining the sensitivity to treatment with PD-L1 targeted therapy.
Elsevier