PD-L1 expression in lung adenocarcinoma harboring EGFR mutations or ALK rearrangements.

Abstract

OBJECTIVES:

Expression of programmed cell death-ligand 1 (PD-L1) has been associated with clinical outcome of programmed cell death-1 (PD-1) pathway blockade in non-small cell lung cancer (NSCLC). The PD-L1 IHC 22C3 pharmDx assay, the only companion diagnostic for pembrolizumab therapy, has revealed that ∼30% of all NSCLCs express PD-L1 at a high level. The frequency of high PD-L1 expression in NSCLCs with known driver oncogenes has remained unclear, however.

MATERIALS AND METHODS:

We retrospectively evaluated PD-L1 expression with the 22C3 assay in tumor tissue of 80 lung adenocarcinoma patients including 71 with EGFR mutations and 9 with ALK rearrangements, all of whom were treated with corresponding tyrosine kinase inhibitors (TKIs).

RESULTS:

Of the 80 tumors analyzed, 26 (32.5%) had a PD-L1 tumor proportion score (TPS) of 1%-49% and 9 (11.3%) had a PD-L1 TPS of ≥50%; 35 (43.8%) thus had a PD-L1 TPS of ≥1%. Of the 71 tumors with EGFR mutations, 23 (32.4%) had a PD-L1 TPS of 1%-49% and 7 (9.9%) had a PD-L1 TPS of ≥50%. A PD-L1 TPS of ≥1% was not associated with any clinical characteristic examined. Progression-free survival on initial TKI treatment was significantly poorer for patients with a PD-L1 TPS of ≥1% than for those with a PD-L1 TPS of <1% (p = .016).

CONCLUSIONS:

A subset of patients with EGFR mutations or ALK rearrangements had a PD-L1 TPS of ≥50%. Prospective studies are thus warranted to examine the efficacy of PD-1/PD-L1 inhibitors in such patients.

• Authors: Yasuto Yoneshima, Kayo Ijichi, Satoshi Anai, Keiichi Ota, Kohei Otsubo, Eiji Iwama, Kentaro Tanaka, Yoshinao Oda, Yoichi Nakanishi, Isamu Okamoto
• Journal: Lung cancer (Amsterdam, Netherlands) (Lung Cancer) Vol. 118 Pg. 36-40 (04 2018) ISSN: 1872-8332 [Electronic] Ireland
• PMID: 29572000 (Publication Type: Journal Article)
• Copyright: Copyright © 2018 Elsevier B.V. All rights reserved.

Chemical References

• B7-H1 Antigen
• CD274 protein, human
• Oncogene Proteins, Fusion
• Anaplastic Lymphoma Kinase
• EGFR protein, human
• ErbB Receptors

Topics

• Adenocarcinoma of Lung (genetics, metabolism, mortality)
• Adult
• Aged
• Aged, 80 and over
• Anaplastic Lymphoma Kinase (genetics)
• B7-H1 Antigen (metabolism)
• ErbB Receptors (genetics)
• Female
• Humans
• Lung Neoplasms (genetics, metabolism, mortality)
• Male
• Middle Aged
• Mutation (genetics)
• Oncogene Proteins, Fusion (genetics)
• Retrospective Studies
• Survival Analysis
• Translocation, Genetic
• Young Adult