Relationship between PDL-1 expression, microenvironment and driver oncogene variations with histopathological features and prognosis in lung adenocarcinoma

Lung cancer is the most common cause of cancer death worldwide. It is more common in men than in women. In addition to diagnosis, preservation of tissue for molecular testing has been recommended by the WHO for targeted treatment options. Recently, immunotherapies targeting Programmed Death-1/Programmed Death Ligand-1 have opened an era in the use of monoclonal antibodies in the treatment of lung cancer. In our study, no significant difference was found in overall survival and progression-free survival between programmed death-ligand -1 high positive, low positive and negative groups. Although some studies conducted in recent years have revealed the relationship between programmed death-ligand -1 expression and driver oncogene alterations in Non Small Cell Lung Cancer, the results are still controversial. In our study, statistical significance was found between the presence of Kirsten Rat Sarkom 2 Viral Onkogen Homolog mutation and high programmed death-ligand-1 expression. The presence of Tumor-infiltrating lymphocytes in tumor stroma is a strong prognostic indicator. A recent study in a large Non Small Cell Lung Cancer cohort showed that dense Tumor-infiltrating lymphocytes infiltration is associated with longer survival and longer disease-free survival. In recent years, tumor-stroma ratio can be used as a prognostic predictor factor and can be used as a descriptive parameter for high-risk lung cancer patients. Progression-free survival time in the group with high tumor-stroma ratio was found to be longer than in the group with low tumor-stroma ratio and was statistically significant. When the distribution of overall survival time according to Tumor Stroma Ratio and Tumor infiltrating lymphocyteslevels was evaluated, no statistically significant relationship was found. When the results of our study were examined, no significant relationship was found between Programmed Death Ligand-1 expression and stromal Tumor infiltrating lymphocytessparse and dense groups. Our study provides a comprehensive perspective on the relationship between Programmed Cell Death Ligand-1 and driver oncogene changes and tumor microenvironment in lung adenocarcinomas.