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Head and neck cancers are the sixth most common cancers worldwide with nearly 680,000 new cases (excluding thyroid cancer) and contributes to a substantial portion of global mortality, with up to 375,000 deaths being attributable to head and neck cancer per year [1]. More than 90% of these cancers are squamous cell carcinomas and variants thereof, originating from the epithelium of the mucosal lining of the upper aerodigestive tract. About two-thirds of diagnosed cases of head and neck cancer are identified in developing countries and this number is expected to grow worldwide because of the adoption of lifestyle behaviours that are known to increase cancer risk, such as indulging in smoking, excessive indulgence in alcohol and maintenance of poor diet [2]. The economic consequences of head and neck cancer in developing countries are significant, and accurate epidemiological studies of the present and future disease is essential to enable improved diagnosis and treatment planning [3, 4].

The differences in the geographic distribution of hypopharyngeal cancer, its analysis and reporting of available data are complicated because of its anatomic sub-sites; the piriform sinus, posterior wall and the post-cricoid regions, and the not infrequent late-stage tumours often being mistaken as laryngeal cancer, thereby resulting is misclassification [5, 6]. Patients diagnosed with “pharyngeal cancer” are uncommon if not rare, representing approximately 5–8% of all cancers of the upper aerodigestive tract [7–9], with the majority (90–95%) being squamous cell carcinoma [7, 8]. The “pharynx” has its own sub-sites: naso-, oro- and hypo-pharynx, and when being reported in the context of the more frequent head and neck sites, oral cavity and larynx, the “pharynx” sub-sites are combined and the incidence reported in geographical cancer publications such as Pan-European [10], Central and South American [11], South Asia [12] and in Global studies [13]. These 3 pharyngeal sub-sites have very different incidences and mixed risk factors contributing to the causation of squamous cell carcinoma: nasopharynx is infected by the Epstein Barr virus, the oropharynx by the human papilloma virus (HPV), and hypopharynx and oropharynx are affected by tobacco and alcohol.