Nasopharyngeal Ca is caused by

NASOPHARYNGEAL CANCER AETIOLOGY :- 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:- Airpollution, smoking of tobacco and opium, nitrosamines from dry salted fish, smoke from burning of incense and wood have all been incriminated. Ref:- Dhingra; pg num:-250