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AETIOLOGY OF NASOPHARYNGEAL CARCINOMA The exact aetiology is not known. The factors responsible are: 1. Genetic. Chinese have a higher genetic susceptibility to nasopharyngeal cancer. Even after migration to other countries they continue to have higher incidence. 2. Viral Epstein-Barr (EB) virus is closely associated with nasopharyngeal cancer. Specific viral markers are being developed to screen people in high-incidence areas. EB virus has two impoant antigens: viral capsid antigen (VCA) and early antigen (EA). IgA antibodies of EA are highly specific for nasopharyngeal cancer but have sensitivity of only 70-80% while IgA antibodies of VCA are more sensitive but less specific. AgA antibodies against both EA and VCA should be done for screening of patients for nasopharyngeal cancer. 3. Environmental. Air pollution, smoking of tobacco and opium, nitrosamines from dry salted fish, smoke from burning of incense and wood have all been incriminated. Ref : ENT textbook by Dhingra 6th edition Pgno : 250