Abstract 1291
Background
The efficacy of immunotherapy treating EGFR-positive non-small cell lung cancer (NSCLC) patients has been proved to be limited. However, a series of mutant-patients could be benefit from PD-1 blockade. Therefore, this study evaluated the immune microenvironment in NSCLC with uncommon EGFR mutation, and explored the prospect of immunotherapy in this cohort.
Methods
We retrospectively evaluated the expression of PD-L1, CD4 and CD8 in NSCLC patients who harbored uncommon EGFR mutation at Zhejiang Cancer Hospital between April 2016 and September 2017. The association with clinical factors and outcomes were also explored, as well as the effectiveness of immunotherapy in uncommon mutation-positive cases.
Results
Among the 600 NSCLC patients with EGFR mutation, we retrospectively collected 49 (8.2%) cases bearing uncommon mutation. In total, 49.0% (24/49) of NSCLC patients showed a strong PD-L1 expression in tumor cells, which was significantly higher than common sensitive (19del and L858R) or negative EGFR mutation (49.0% vs 12.1% vs 26.3%, respectively, P < 0.05). Furthermore, positive PD-L1 expression was associated with a significantly shortened OS when compared with the negative PD-L1 expression (20.0 vs 44.3 months, P = 0.006). And PD-L1 positivity was predominantly observed among patients with high CD8 expression rather than low cases (72.0% vs 25.0%, P = 0.001). Notably, we found PD-L1 and CD8 dual-positive cases demonstrated the worst prognosis (OS: 19.3[dual-positive] vs 31.1[single-positive] vs 44.3[dual-negative] months, P = 0.023). Additionally, this approach revealed PD-L1 and CD8 positivity were not associated with the response to EGFR-TKIs, playing no role in the de novo resistance of EGFR-TKIs among the uncommon mutated patients. Finally, one patient harboring EGFR G719A mutation with PD-L1 and CD8 dual positivity experienced a favorable response to anti-PD-1 therapy.
Conclusions
This study revealed the expression of PD-L1, CD4 and CD8 in uncommon EGFR-mutated NSCLC patients. The findings indicated the reshaping of an inflamed immune phenotype characterized by PD-L1 and CD8 dual positivity and suggest potential therapeutic sensitivity to PD-1 blockade.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
5071 - Expression of estrogen receptor and programmed cell death-ligand 1 can be complementary prognostic factors in HPV-positive oropharyngeal squamous cell carcinoma
Presenter: Soohyeon Kwon
Session: Poster Display session 3
Resources:
Abstract
5306 - Real-world data of clinicopathologic characteristics of young oropharyngeal cancer patients.
Presenter: Maria Nieva
Session: Poster Display session 3
Resources:
Abstract
3407 - The clinical significance and biological mechanisms of miR-499a in high-tobacco exposed head and neck squamous cell carcinoma
Presenter: Shiqi Gong
Session: Poster Display session 3
Resources:
Abstract
3310 - Liquid biopsy for mutational profiling of locoregional recurrent and/or metastatic squamous cell carcinoma of the head and neck
Presenter: Rachel Galot
Session: Poster Display session 3
Resources:
Abstract
2362 - Blood-based testing of mutations in patients with Head and neck squamous cell carcinoma (HNSCC) using highly sensitive SafeSEQ technology
Presenter: Florentia Fostira
Session: Poster Display session 3
Resources:
Abstract
4533 - The head and neck Lung Immune Prognostic Index (HN-LIPI): a prognostic Score for Immune Checkpoint Inhibitors (ICI) in Recurrent or Metastatic Squamous Cell Carcinoma of the Head and Neck (R/M SCCHN) patients.
Presenter: Ruth Gabriela Herrera Gomez
Session: Poster Display session 3
Resources:
Abstract
5262 - Immune-related adverse events (irAEs) and outcome in recurrent/metastatic (R/M) Head and Neck Squamous Cell Carcinoma (HNSCC) patients (pts) treated by immune-checkpoints inhibitors (ICI)
Presenter: Neus Baste Rotllan
Session: Poster Display session 3
Resources:
Abstract
3725 - Intratumoral and peripheral exploratory biomarker analysis in patients with locoregional, recurrent head and neck squamous cell carcinoma (rHNSCC) treated with RM-1929 photoimmunotherapy
Presenter: Jack Bui
Session: Poster Display session 3
Resources:
Abstract
2533 - A nomogram based prognostic score to predict overall survival (OS) in recurrent-metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) patients (pts) treated with immune checkpoint inhibitors (ICI).
Presenter: Luay Mousa
Session: Poster Display session 3
Resources:
Abstract
2929 - Changes of the Commensal Microbiome during Treatment are Associated with Clinical Response in the Nasopharyngeal Carcinoma Patients
Presenter: Tingting Huang
Session: Poster Display session 3
Resources:
Abstract