HEAD AND NECK MALGNANCIES
Cancers of the head and neck are difficult to characterise since this heterogenous group of tumours occur in different though anatomically related sites in the head and neck region, extending from the oral cavity , the nose/sinuses to the pharynx and larynx. However these tumours tend to have one thing in common – histologically most malignant growths are squamous cell carcinoma, up to 90% (with the exception of tumours of salivary glands). Lymphomas and sarcomas do occur but usually in the minority in most reported series. Indeed head and neck squamous carcinomas (HNSCC) are variously reckoned to be 6th to 10th in worldwide incidence of cancers, with over half a million new cases annually ; males are more affected, mainly in the fifties and sixties in age.
Reports suggest that most cases of primary HNSCC occur in the industrialised countries, no doubt on account of association with certain environmental and life-style risk factors such as tobacco smoking , alcohol and some industrial chemicals and wood dust. However HNSCC are not uncommon in the West African sub-region where these risk factors are also increasingly present. Furthermore certain viruses, in particular human papilloma virus (HPV) and Ebstein-Barr virus which are linked with upper aero-digestive tumours are prevalent here. Some other dietary habits such as chewing of tobacco and betel/other nuts, as well as consumption of salted fish (in relation to nasopharyngeal cancer particularly) may also be relevant. It is however important to note that many risk factors impact to variable degrees on anatomically contiguous but epidermiologically and oncologically distinct head and neck sites.
Reliable statistics are difficult to come by in this region, since most published reports are confined to the more common malignancies of the nasopharynx, sino-nasal complex and the larynx3,4,5. Even with the customary exclusion of ophthalmic and intracranial conditions, there is a large spectrum of neoplasms in the region that also include the ears, oropharynx, hypopharynx and even the thyroid. Because of limited experience in individual institutions large multicentre studies will be required in future to correct this deficiency.
Head and neck cancers generally present late in our practices due, in part, to the often confusing and nonspecific early symptoms and late diagnosis, in an environment of ignorance, poverty and limited specialist medical facilities. The frequent spread to regional lymph-nodes may be an early signpost, but a high index of suspicion is often needed for early diagnosis; experience has shown that early institution of definitive treatment greatly improves cure rate and prognosis , which is about 40 - 50% 5-year survival on average. It is also true that appropriate surgical skills based on familiarity with the crowded anatomy of this region will no doubt contribute to improved treatment results. In this regard the current emphasis on head and neck dissection courses and workshops for trainee residents and young consultants, mainly under the auspices of the postgraduate colleges, is very relevant and is to be encouraged.
For tumours in most of the sites surgery and radiotherapy are the applicable modalities of treatment , depending on initial extent of tumour. Indeed for the more common nasopharyngeal, sino-nasal and laryngeal growths high cure rates are achievable with surgery and/or chemo-irradiation in early cases6. Surgery in late cases, even augmented by neck dissection and reconstruction, has uniformly poor outcomes and in such patients radiotherapy is at best palliative.
Although the wide variety of symptomatology of head and neck tumours are also more commonly attributable to benign conditions, it is none the less possible with careful clinical evaluation and an index of suspicion in individual cases to identify unusual trends that will point to correct diagnosis. Advances in radio-diagnostic techniques now provide greater assistance in evaluation as well as staging of cases. The desirable aim must be to “catch them early”.
References
- Morton PP, Izzard ME. Epidermiology of Head and Neck cancer. In – Scott-Brown’s Otorhinolaryngology , Head and Neck Surgery(Ed. Micheal Gleeson ) 7th Ed. Hodder Arnold, London . 2008; Vol. 2 : 2343 – 2349.
- American Cancer Society . Cancer facts and figures 2014.
- Adoga AS, John EN, Yiltok SJ, Echejoh GO, Nwaorgu OGB. The pattern of head and neck tumours in Jos. Highland Medical Research Journal . 2009 Vol. 8(1).
- Okolugbo NE, Ogisi FO. Nasopharyngeal carcinoma in Benin-City Nigeria. Eur. Arch. Otorhinolaryngol. 2007 (Suppl. 1) 264: S1 – S151.
- Nwaorgu OGB, Ogunbiyi JO. Nasopharyngeal Cancer at the University college Hospital Ibadan Cancer Registry: an update. West African Journal of Medicine 2004 Vol. 23(2) : 135 – 138.
- Okolugbo NE, Ogisi FO. Surgery in the management of Cancer of the larynx in Benin. Journal of Medicine and Biomedical Research. 2006. Vol. 5(1); 13 – 15.
Professor Festus O. Ogisi FWACS.
Consultant ENT/Head & Neck Surgeon,University of Benin Teaching Hospital,
Benin City,
Nigeria.
E-mail: