Head and neck cancer: treatment of nasopharyngeal cancer.

Nasopharyngeal carcinoma (NPC) is a rare disease in most parts of the world, with an age-standardised annual incidence of less than 1 per 100 000. However, in Southern China, parts of Southeast Asia and the Mediterranean basin, NPC is an endemic disease with an incidence of 10–30 per 100 000 [1]. The three major well-defined aetiological factors for NPC include genetically determined susceptibility, early-age exposure to chemical carcinogens particularly of Southern Chinese salted fish, and association with a latent Epstein– Barr virus (EBV) infection [2]. Three histopathological types are recognised in the WHO classification [3]. Type I is squamous cell carcinoma with varying degrees of differentiation, type II is non-keratinising carcinoma and type III is undifferentiated carcinoma. WHO types II and III can be considered together as undifferentiated carcinoma of the nasopharyngeal type (UCNT), which accounts for >95% of cases in endemic areas and 50% of cases in non-endemic areas. The histological subtype may be of prognostic significance, with UCNT having a higher local control rate after treatment with radiotherapy and a higher propensity for development of distant metastases [4].