EVIDENCE OF EPSTEIN-BARR VIRUS ASSOCIATION WITH HEAD AND NECK CANCERS: A REVIEW.

Epstein-Barr virus (EBV) is ubiquitous: over 90% of the adult population is infected with this virus. EBV is capable of infecting both B lymphocytes and epithelial cells throughout the body including the head and neck region. Transmission occurs mainly by exchange of saliva. The infection is asymptomatic or mild in children but, in adolescents and young adults, it causes infectious mononucleosis, a self-limiting disease characterized by lethargy, sore throat, fever and lymphadenopathy. Once established, the virus often remains latent and people become lifelong carriers without experiencing disease. However, in some people, the latent virus is capable of causing malignant tumours, such as nasopharyngeal carcinoma and various B- and T-cell lymphomas, at sites including the head, neck and oropharyngeal region. As lymphoma is the second-most common malignant disease of the head, neck and oral region after squamous cell carcinoma, oral health care workers including dentists and specialists have a responsibility to carry out a thorough clinical examination of this anatomical region with a view to identifying and diagnosing lesions that may represent lymphomas. Early detection allows early treatment resulting in better prognosis. The focus of this review is on the morphology, transmission and carcinogenic properties of EBV and clinical and diagnostic aspects of a range of EBV-associated malignancies occurring in the head, neck and oral region. As carcinogenic agents, viruses contribute to a significant proportion of the global cancer burden: approximately 15% of all human cancers, worldwide, are attributable to viruses.1,2 Serologic and epidemiologic studies are providing mounting evidence of an etiologic association between viruses and head and neck malignancies.3 To update oral and maxillofacial surgeons and oral medicine specialists and raise awareness of this association, we recently reviewed the evidence of the etiologic role of human papillomavirus in oral disease.4 In this paper, we review the current state of knowledge of the association of Epstein-Barr virus (EBV) with malignant diseases in the head and neck region.