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The annual incidence is around 1/100 000 in Western countries. Incidence is higher in the Chinese and Tunisian populations. Although rare, NPC accounts for about one third of childhood nasopharyngeal neoplasms.

Three subtypes of NPC are recognized in the World Health Organization (WHO) classification: 1) squamous cell carcinoma, typically found in the older adult population; 2) non-keratinizing carcinoma; 3) undifferentiated carcinoma. The tumor can extend within or out of the nasopharynx to the other lateral wall and/or posterosuperiorly to the base of the skull or the palate, nasal cavity or oropharynx. It then typically metastases to cervical lymph nodes. Cervical lymphadenopathy is the initial presentation in many patients, and the diagnosis of NPC is often made by lymph node biopsy. Symptoms related to the primary tumor include trismus, pain, otitis media, nasal regurgitation due to paresis of the soft palate, hearing loss and cranial nerve palsies. Larger growths may produce nasal obstruction or bleeding and a 'nasal twang'.

Etiological factors include Epstein-Barr virus (EBV), genetic susceptibility and consumption of food with possible carcinogens - volatile nitrosamines.

Diagnostic methods include indirect nasopharyngoscopy to assess the primary tumor, clinical evaluation of the size of cervical lymph nodes and biopsy of either the lymph nodes or primary tumor for histological examination. Other potential sites of metastasis are further investigated by neurological examination of cranial nerves, computed tomography (CT)/magnetic resonance imaging (MRI) scan of the head and neck, chest radiotherapy and bone scintigraphy. EBV viral capsid antigen and EBV DNA can be detected by serum analysis.

The recommended treatment schedule consists of three courses of neoadjuvant chemotherapy, irradiation, and adjuvant interferon (IFN)-beta therapy.

Presentation with lymphadenopathy implies that the disease has spread beyond the primary site. However, in childhood, the presence of metastatic disease in cervical lymph nodes at diagnosis does not adversely affect prognosis. Factors associated with a poor prognosis are skull base involvement, extent of the primary tumor and cranial nerve involvement.