Expression of Programmed Death Ligand-1 (PD-L1) in Nasopharyngeal and Hyypopharyngeal Carcinoma

Head and neck tumors comprise heterogeneous neoplasms that arise from surface epithelium of different anatomic subsites in head and neck region such as oral cavity, oropharynx, larynx and hypopharynx. Nasopharyngeal and hypopharyngeal carcinomas represent 0.26 % of all cancers in Egypt. Tobacco exposure and alcohol dependence, and infection with oncogenic viruses such as human Papilloma virus (HPV) are among the risk factors for development of these tumors. Currently, the main treatment of nasopharyngeal and hypopharyngeal carcinomas is radio-chemotherapy based in histological type, grade and stages of the tumors

Tumor infiltrating lymphocytes (TILs) are considered as cornerstone in cancer immunotherapy and as a biomarker with effectiveness predictive value. The intensity and quality of immune cells, especially lymphocytes, in tumor microenvironment are strongly related to the outcome of immune checkpoint blockade therapy .