Programmed death-ligand 1 (PD-L1) is the most widely utilized predictive marker used to identify non-small cell lung carcinoma (NSCLC) patients most suitable for immunotherapy approaches. The relationship between PD-L1 expression, the presence of CD8+ T cells, and other clinicopathological characteristics of NSCLC patients has not been elucidated yet. In this retrospective study, we immunohistochemically determined PD-L1 expression (using clone 22C3) and CD8+ T cell count (using clone c8/144B) in surgical resection specimens from 698 advanced NSCLC patients.
View Article and Find Full Text PDFPleomorphic carcinomas are known to be highly programmed death ligand 1 (PD-L1) positive non-small cell lung cancer (NSCLC) types. However, the level of PD-L1 expression in lung carcinomas with a minor sarcomatoid component, comprising less than 10 % of the tumor mass, has not been determined yet. We hypothesized that NSCLC with a minor sarcomatoid component is more closely related to pleomorphic carcinomas in terms of PD-L1 expression than to NSCLC types without sarcomatoid features.
View Article and Find Full Text PDFIntratumoural heterogeneity of pulmonary adenocarcinoma challenges the accurate interpretation of programmed death ligand 1 (PD-L1) immunohistochemistry, which is the only validated predictive marker for successful anti-PD-1/PD-L1 immunotherapy. The aim of this study was to determine whether PD-L1 expression is related to adenocarcinoma histological differentiation in a retrospective analysis of tumour biopsies with intratumoural histological heterogeneity. Adenocarcinomas with high intratumoural heterogeneity were categorised as 'mixed adenocarcinomas'.
View Article and Find Full Text PDFIntroduction: Recent studies on check-point inhibitor therapy, which seems to improve the prognosis of patients with advanced non-small cell lung carcinoma increase the importance of immunohistochemical analyses of the programmed-death receptor and of its ligand, PD-L1 protein.
Material And Methods: In our study we present results of PD-L1 immunohistochemical tumor cell expression in a series of 325 lung carcinoma patients biopsies, using the clone 22C3 (and DAKO Link 48 immunostainer). Evaluation of the expression using tissue proportion scoring system allowed to distinguish negative cases (either 0 % or < 1 % of positive tumor cells) versus positive cases in the categories 1-9 %, 10-49 % and ≥ 50 % of positive tumor cells.