Programmed Cell Death Ligand 1 Expression in Cytological and Surgical Non-Small Cell Lung Cancer Specimens in Association with EGFR Mutation and Overall Survival: A Single-Institution Experience

• Published in: Turk patoloji dergisi Vol. 38; no. 3; pp. 261 - 274
• Main Authors: Gokal, Elif Sayman, Aker, Fugen Vardar, Silav, Zuhal Kus, Oven, Bala Basak
• Format: Journal Article
• Language: English
• Published: Turkey Akdema Informatics and Publishing 01.09.2022; Federation of Turkish Pathology Societies
• Subjects: Apoptosis; Biochemistry; Comparative analysis; Epidermal growth factor; epidermal growth factor receptor; Genetic aspects; Ipilimumab; Lung cancer, Non-small cell; Lung cancer, Small cell; Medical research; Medicine, Experimental; non-small cell lung cancer; Original; Patient outcomes; programmed cell death ligand-1; survival
• ISSN: 1018-5615; 1309-5730
• DOI: 10.5146/tjpath.2022.01572

The aim of this study was to evaluate programmed cell death ligand-1 (PD-L1) expression and the relationship between driver mutations and survival analysis in advanced-stage non-small cell lung carcinoma (NSCLC). A total of 122 advanced-stage NSCLC patients were included in this retrospective study. The patients were diagnosed based on cytological examination and histopathological analysis of biopsy or resection material that had undergone at least 1 molecular analysis. The expression of PD-L1 in tumors and tumor-infiltrating lymphocytes (TIL) was scored and compared with age, sex, organ, biopsy method, tumor subtype, driver mutation status, and overall survival data. There was no statistically significant difference between PD-L1-positivity and age, gender, location, pattern, or pathological diagnosis of the type of sample. When the threshold value for PD-L1 IHC evaluation was accepted as ≥1% and ≥50%, the rate of positivity was 19.7% and 7.4%, respectively. Since there is a wide range of positivity rates reported in the literature, we could not reach a conclusion as to whether the PD-L1-positivity rate we observed was high or low. There is a need for comparative studies where the technique, clones, threshold values, and phases are homogenized. There is an inverse correlation between the EGFR-mutant population and PD-L1 positivity. In terms of overall survival, no relationship was found between PD-L1 positivity, the presence of TIL, and EGFR mutation status.