Abstract
Introduction: To improve the prognosis of lung cancer patients, immunotherapy is expected to become a powerful therapeutic option. Several clinical studies demonstrate a positive prognostic effect of a targeted therapy against the programmed cell death receptor PD1 and its ligand PDL1 in solid tumors. For non-small lung cancer (NSCLC) however, the diagnostic, prognostic and predictive impact of these factors needs to be clarified.
Materials and Methods: Immunohistochemistry was performed to evaluate the expression profile of PD1 and PDL1 in 398 NSCLC patients (median age: 66 years, 78% male sex, 45% squamous cell carcinoma (SCC) histology). Statistical analysis included Fisher's Exact test, univariate and multivariate models.
Results: 23% of the NSCLC samples expressed PDL1 and 11% of the investigated tumors displayed PD1 in tumor infiltrating lymphocytes (TILs). A positive correlation with PD1-positive lymphocytes was found for male sex (p=0.022), age below 70 years (p=0.039), adjuvant therapy (p=0.018) and Bcl-2 protein expression (p=0.012). PDL1 was associated with increased overall survival in SCC (p=0.031, log rank test; p=0.007, multivariate cox regression model: HR(95%CI)= 0.494(0.296-0.825)).
Conclusion: In the context of immunotherapeutic approaches we present a histology-depending prognostic effect of PDL1 for NSCLC patients with SCC. With regard to the observed effect, further studies are required to evaluate the prospective impact of PD1 and PDL1 in NSCLC.
- Copyright ©ERS 2015
