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What is Nasopharyngeal Carcinoma is caused by and explain in detail?
AETIOLOGY The exact aetiology is not known. The factors responsible are: 1. Genetic. Chinese have a higher genetic susceptibility 2. Viral. Epstein-Barr (EB) virus is closely associated with nasopharyngeal cancer. 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 a sensitivity of only 70-80% while IgA antibodies of VCA are more sensitive but less specific. 3. Environmental. Air pollution, smoking of tobacco and opium, nitrosamines from dry salted fish, smoke from the burning of incense and would have all been incriminated. (Ref: Diseases of Ear, Nose and Throat, P.L Dhingra, 7th edition, page 283)