The Evolving Concept of Viruses and Immune System Interaction in Head and Neck Neoplasms

Head and neck squamous cell carcinoma (HNSCC) is a malignant tumor with a poor prognosis and a high relapse rate, known to be associated with viral infections, in most cases with high-risk strains of human papilloma virus (HPV). The therapeutic approach does not always allow the eradication of the disease, especially in advanced and metastatic stages, making it necessary to identify new therapeutic targets. The study of the tumor microenvironment and its intrinsic dynamic is becoming increasingly important, given the encouraging results obtained by immunotherapy, in the context of HNSCC as well as of other cancers. In this chapter, we will describe the current knowledge on viral pathogenesis of HNSCC, the interactions between tumor cells, viruses, and microenvironment with the related mechanisms of immune evasion and applications of immunotherapy. The attempt is to explore the new potential applications and limits of immunotherapy in HNSCC, in search of new approaches and therapeutic targets. Understanding of the crosstalk between the cancer cells and the host immune system is crucial in effectively treating HNSCC and many efforts should be spent to evaluate its immunology and biology as a complex and rapidly developing area. In this way, novel therapies will be developed to overcome the resistance mechanisms and improve patient outcome.