Epidemiology and Etiology of Nasopharyngeal Carcinoma: Gene-Environment Interaction

There are striking ethnic and geographical variations in risk of nasopharyngeal carcinoma (NPC). Males have a higher NPC risk than females in all populations, and high risk populations have a younger peak age at onset than low risk populations. Epstein-Barr virus infection has been consistently documented to be associated with an increased risk of NPC. Dietary factors, especially Cantonese salted fish and preserved foods, are important risk factors for NPC. Cigarette smoking, occupational exposures to wood dust, formaldehyde and chemical fumes, use of Chinese herbs are also associated with NPC. There is a strong familial tendency of NPC. Genetic polymorphisms of human leukocyte antigens and some enzymes involved in xenobiotic metabolism and DNA repair are associated with NPC. Both segregation and linkage analyses have implied the inheritance mode and location of susceptibility genes of NPC. NPC is the result of a multistage process with a multi-factorial etiology of gene-environment interactions.