The Co-Expression of Programmed Death-Ligand 1 (PD-L1) in Untreated EGFR-Mutated Metastatic Lung Adenocarcinoma
Ping-Chih Hsu1, Chih-Wei Wang2, Scott Chih-Hsi Kuo1
1Division of Thoracic Medicine, Department of Internal Medicine, Chang Gung Memorial Hospital at Linkou, Chang Gung University College of Medicine, Taoyuan City 33305, Taiwan.
Abstract:
Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) is the standard first-line therapy for metastatic lung adenocarcinoma harboring sensitive EGFR mutations. Tumor surface programmed death-ligand 1 (PD-L1) is expressed in some metastatic EGFR-mutated lung adenocarcinoma, but its impact on the efficacy of EGFR-TKIs is unclear. We retrospectively investigated 117 untreated metastatic lung EGFR mutated adenocarcinoma patients with a PD-L1 immunohistochemistry test. The PD-L1 expression level was classified by tumor proportion scores (TPS). Forty-five patients had negative expression (TPS < 1%), 45 had a weak expression (TPS 1-49%), and 27 had a strong expression (≥50%). All patients recruited in this study received EGFR-TKIs as a first-line therapy. No significant differences were observed for objective response rates (68.9% versus 62.2% versus 73.1%, p = 0.807) and median time to treatment failure (TTF) (12.17 versus 13.17 versus 11.0 months, p = 0.443) of first-line EGFR-TKIS among the three groups of patients (negative versus weak versus strong). The median overall survival was 21.27 versus 20.63 versus 19.43 months among the three groups of patients (p = 0.77). Our results demonstrated that PD-L1 did not affect the efficacy of first-line EGFR-TKIs in metastatic EGFR mutated lung adenocarcinoma. Thus, EGFR-TKIs are suggested as the preferred clinical therapy for these patients, despite their PD-L1 levels.
Insights
Programmed death-ligand 1 (PD-L1) expression does not impact the effectiveness of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) in treating metastatic EGFR-mutated lung adenocarcinoma. EGFR-TKIs remain the preferred first-line therapy regardless of PD-L1 levels.
Area of Science:
- Oncology
- Medical Research
- Translational Medicine
Background:
- Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) are standard first-line treatment for metastatic lung adenocarcinoma with EGFR mutations.
- The role of tumor surface programmed death-ligand 1 (PD-L1) expression in the efficacy of EGFR-TKIs for these patients is not well understood.
Purpose of the Study:
- To investigate the impact of PD-L1 expression levels on the efficacy of first-line EGFR-TKIs in patients with metastatic EGFR-mutated lung adenocarcinoma.
Main Methods:
- Retrospective analysis of 117 untreated metastatic lung adenocarcinoma patients with EGFR mutations and PD-L1 testing.
- Patients were categorized into three groups based on PD-L1 tumor proportion score (TPS): negative (<1%), weak (1-49%), and strong (≥50%).
- Efficacy outcomes including objective response rates (ORR), time to treatment failure (TTF), and overall survival (OS) were compared across PD-L1 expression groups.
Main Results:
- No significant differences in ORR (p=0.807), median TTF (p=0.443), or median OS (p=0.77) were observed among patients with negative, weak, or strong PD-L1 expression.
- Objective response rates were 68.9% (negative), 62.2% (weak), and 73.1% (strong).
- Median TTF was 12.17 months (negative), 13.17 months (weak), and 11.0 months (strong). Median OS was 21.27 months (negative), 20.63 months (weak), and 19.43 months (strong).
Conclusions:
- PD-L1 expression levels do not influence the efficacy of first-line EGFR-TKIs in metastatic EGFR-mutated lung adenocarcinoma.
- EGFR-TKIs are recommended as the preferred first-line therapy for these patients, irrespective of their PD-L1 status.
