Abstract 106P
Background
Lung cancer is the leading cause of cancer-related mortality worldwide, accounting for 1.8 million deaths in 2018. The discovery of a valid biomarker for this dreaded disease remains elusive. Advances in tumor immunology have shed light on the vital role of immune checkpoint proteins in regulating tumorigenesis, antitumor immunity and immune evasion. This meta-analysis and systematic review investigated the prognostic value of immune checkpoint proteins in patients with non-small cell lung cancer.
Methods
Pertinent studies were gathered via electronic search of PubMed, EMBASE, MEDLINE, Web of Science, Google Scholar and Cochrane Library databases up to April 30, 2020. Utilizing Review Manager 5.3, pooled hazard ratios and 95% confidence intervals were calculated using random or fixed effects models, contingent on the heterogeneity of studies.
Results
A total of 17 studies involving 6179 patients were included. Pooled analysis revealed that high PD-L1 expression was significantly associated with lower overall survival (OS), with a hazard ratio of 1.22 (95% CI, 1.06 – 1.41; p = 0.005). Subgroup analysis showed that high PD-L1 expression was significantly correlated with improved OS among patients given immune checkpoint inhibitors (HR, 0.40; 95% CI, 0.23 – 0.70; p = 0.001), albeit with worse OS among patients given adjuvant chemotherapy (HR, 1.27; 95% CI, 1.13 – 1.42; p < 0.0001). High PD-1 expression was significantly associated with inferior OS (HR, 1.23; 95% CI, 1.03 – 1.57; p = 0.02). Subgroup analysis based on tumor subtype showed that high PD-1 expression correlated with inferior OS among patients with adenocarcinoma (HR, 1.50; 95% CI 1.04 – 2.16; p = 0.03), but not among patients with squamous cell cancer. High IDO1 expression portends improved OS (HR, 0.72; 95% CI, 0.52 – 0.98; p = 0.04), while high LAG3 expression was not significantly associated with OS.
Conclusions
Immune checkpoint proteins can potentially prognosticate survival outcomes of patients with non-small cell lung cancer. Prospective studies that explore the role of immune checkpoint proteins in non-small cell lung cancer are encouraged to help improve the survival rates of patients afflicted with this deadly disease.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
G.D.H. Cornelio: Advisory/Consultancy: AstraZeneca. All other authors have declared no conflicts of interest.