PD-L1 expression according to the EGFR status in primary lung adenocarcinoma. (February 2018)

• Record Type: Journal Article
• Authors: Takada, Kazuki; Toyokawa, Gouji; Tagawa, Tetsuzo; Kohashi, Kenichi; Shimokawa, Mototsugu; Akamine, Takaki; Takamori, Shinkichi; Hirai, Fumihiko; Shoji, Fumihiro; Okamoto, Tatsuro; Oda, Yoshinao; Maehara, Yoshihiko
• Is Part Of: Lung cancer. Volume 116(2018)
• Page Start: 1
• Page End: 6
• Publication Date: 2018-02
• Subjects: PD-L1 -- EGFR -- Lung adenocarcinoma; Lungs -- Cancer -- Periodicals; Lung Neoplasms -- Abstracts; Lung Neoplasms -- Periodicals; Poumons -- Cancer -- Périodiques; Lungs -- Cancer; Periodicals; Electronic journals; Electronic journals; 616.99424
• DOI: 10.1016/j.lungcan.2017.12.003
• Languages: English
• ISSNs: 0169-5002

Abstract

Highlights: Association between PD-L1 expression and EGFR mutation site is poorly reported. We investigated the association between PD-L1 expression and EGFR status. PD-L1 expression was significantly associated with wild-type EGFR . PD-L1 TPS ≥50% seldom overlaps with the presence of driver oncogene EGFR . There was no significant difference in PD-L1 expression among EGFR mutation sites. Abstract: Objectives: It was reported that programmed cell death-ligand 1 (PD-L1) expression is associated with smoking and wild-type epidermal growth factor receptor ( EGFR ) in lung adenocarcinoma. However, the association between PD-L1 expression and EGFR mutation site in EGFR mutation-positive lung adenocarcinoma is unclear. Materials and methods: We retrospectively examined the relationship between PD-L1 expression and EGFR status in 441 surgically resected primary lung adenocarcinomas. Membrane PD-L1 expression on tumor cells was evaluated by immunohistochemical analysis using a PD-L1 antibody (clone SP142) and defined by tumor proportion scores (TPSs) of 0%, 1–4%, 5–49%, and ≥50%, respectively. Results: Two hundred and eighteen (49.4%) patients had wild-type EGFR, and 223 (50.6%) had mutant EGFR —98 (44.0%) with exon 19 deletion, 116 (52.0%) with exon 21 L858R point mutation, and nine (4.0%) with another EGFR mutation. Overall, Fisher's exact test showed that PD-L1 positivity was associated with wild-type EGFR, and there was only one case with PD-L1 TPS ≥50% among the cases with mutant EGFR . The analysis of cases with mutant EGFR indicated no significant association between EGFR mutation site and PD-L1 expression. However, the prevalence of PD-L1 TPS 5–49% was higher among patients with EGFR exon 19 deletion than with EGFR exon 21 L858R point mutation. Conclusions: PD-L1 expression was significantly associated with wild-type EGFR, and PD-L1 TPS ≥50% seldom overlaps with presence of driver oncogene EGFR . There was no significant difference in PD-L1 expression among the EGFR mutation sites