PD-L1 and CD8-Tumor-Infiltrating Lymphocytes Expression in Laryngeal Squamous Cell Carcinoma

Abstract

Studies in recent years have shown that the immune system plays an important role in the prognosis of patients with different types of malignancies. The tumor immune microenvironment has been studied in various cancers in an attempt to find new antitumoral therapies. The therapeutic blockade of PD-1/PD-L1 has revolutionized the treatment of oncological pacients, with anti-PD-L1 monoclonal antibodies having remarkable results in malignant melanoma, cervical, renal and lung cancer. In laryngeal cancer, few reports are available on the immune microenvironment and PD-L1 expression. Considering these, we retrospectively review 23 laryngeal cancer patients with laryngectomy performed in the Otorhinolaryngology Department - Emergency County Clinical Hospital St Andrew Constanta. The aim of our research was to evaluate the immunohistochemical expression of PD-L1, using combined positive score which includes both viable tumoral cells and intratumoral lymphocytes, as well as the level of CD8 intratumoral lymphocytes and to analise the corelation between these markers and the clinicopathological characteristics of the pacients, in order to set these two parameters, in the near future, as new biomarkers. PD-L1 expression was shown to be a prognostic factor for disease-free survival in laryngeal cancer patients (p = 0.006) and was higher in tumors with elevated CD8 lymphocyte levels, with a significant correlation correlation between the two parameters (p = 0.019). The level of CD8 lymphocytes was also a predictive factor for free-disease survival, correlated with patient smoker status (p = 0.04), being higher in non-smoking patients.