Survival rates good if it has not reached the supraclavicular fossal lymph nodes. Good example of the interplay of viral, genetic and environmental factors. Consumption of salted fish in endemic regions is high. These are thought to contain high levels of phorbol esters and nitrosamines. Genetic studies have shown a loss of heterozygosity in several chromosomal regions thought to contain a susceptibility locus.
Most carcinomas have a prolonged dysplasia-carcinoma in situ phase.
But not in NPC, viral gene expression is thought to result in a rapid clonal expansion of cells and invasive neoplasia. In post transplant lymphoma a reduction in immunosupression therapy may induce regression. Mutations are not found in Rb or p53 in EBV associated tumours. More than 200 million infected worldwide. Symptoms are managed during the acute phase.