Epstein-Barr virus and undifferentiated nasopharyngeal carcinoma: new immunobiological and molecular insights on a long-standing etiopathogenic association.

Undifferentiated nasopharyngeal carcinoma (UCNT) is characterized by its unique epidemiologic, immunobiologic, virologic, and clinicopathologic features. Aside from environmental risk factors and possible genetic susceptibility, infection by the Epstein-Barr virus (EBV) constitutes a well-documented link for the development of UCNT. However, despite the fact that UCNT is the human tumor associated most consistently with EBV, the role played by this virus in the pathogenesis of UCNT is still largely speculative and is a matter of ongoing debate. The purpose of this article is to review recent advances, particularly at the immunovirological and molecular levels, linking EBV infection to UCNT, and to discuss those aspects that may be of relevance for a better diagnosis and/or prognosis of this tumor, as well as for development of novel therapeutic strategies.