Prospective Non Interventional Study Evaluating Prognostic and Predictive Value of PDL-1 Expression and Associated T-cell Infiltration in Primary Laryngeal Squamous Cell Carcinoma

Abstract

n Egypt, 1029 new cases were diagnosed in 2018 and 910 cases died in 2018 from head and neck cancers. The most significant risk factor for laryngeal cancer development is tobacco smoking; with synergistic increase in laryngeal cancer incidence when associated with alcohol abuse. Squamous cell carcinoma (SCC) and its variants represent the most common malignancy in head and neck. Two major pathways are implicated in the development of invasive SCC in the head and neck: tumors related to tobacco and alcohol and those associated with human papilloma virus (HPV). The accumulation of genetic and epigenetic changes and abnormalities in cancer associated signaling pathways are the main causes for development of various types of cancers including HNSCC. Immune system plays a main role in protecting our bodies from cancers and rejecting it. However cancer cells affect the immune system and use its components to promote its growth and survival. T- lymphocytes are considered the crucial component of antitumor immunity, with CD8+ T cells serving as cytotoxic effector cells. There must be a balance in controlling cytotoxic T cells (CTLs) activation and inhibition. Some checkpoint proteins on CTLs help them to become fully active. These are the activating checkpoint proteins. CTLs also display on their surface a range of inhibitory checkpoint proteins.