Oropharyngeal Cancers : Where do we stand today ?

Head and neck cancers comprise approximately 5% of the global cancer burden, with an estimated 686000 new cases diagnosed every year, and with approx

375000 new cancer related deaths .

In India Head and neck cancer incidence is ~56,000 accounting for 20% of all

cancer . Oropharyngeal cancers account approximately 10 % of annual

worldwide incidence of head and neck squamous cell carcinomas .

Oropharyngeal squamous cell carcinoma (SCC) comprises 20-25% of all

head and neck cancers in India .The incidence of oropharyngeal carcinoma

is increasing in contrast to decrease in incidence of head and neck cancer

arising in other anatomic sites.

Incidence rates are higher in males than females and diagnosed commonly in sixth or seventh decades of life.

The etiological factors are mainly alcohol and smoking. Tobacco smoking and alcohol drinking separately increase the risk of oral and pharyngeal cancer. Increased risk is with both filtered and non-filtered smoke. Heavy consumers of all types of alcohol are at increased risk of oropharyngeal cancer, the risks are greatest for hard liquor and beer and least for wine drinkers . There is increase in oropharyngeal cancers in non-smokers and non-drinkers which are found to be associated with Human papilloma virus (HPV). Sub sites of oropharynx are soft palate and uvula, base of tongue, vallecula, tonsillar region and oropharyngeal wall.

Clinical presentation is for symptoms like odynophagia, dysphagia, otalgia, neck mass, halitosis, trismus (in very locally advanced stages).

Patients in the developing world like India tend to present in advanced stages,

with a greater burden of both primary and neck nodal disease.

It represents a significant economic, social, and psychological burden and

morbidity with the mortality.

Critical function of oropharynx in speech and swallowing mandates careful consideration while opting for treatment modality to preserve quality of life. High cure rate as well as minimal possible morbidity is the overall treatment aim.

Early stage oropharyngeal cancers are managed with single modality therapy (radiation / surgery) based on considering post treatment consequences. For locally advanced oropharyngeal carcinoma standard of care is concurrent chemoradiation. Traditionally radiation therapy (RT) was given with bilateral portals covering the primary disease as well as the nodal sites.

However more recently conformal techniques of radiation such as intensity

modulated radiation therapy (IMRT) and image guided radiation therapy

(IGRT) have shown improved control rates and reduction in the toxicity .

Radical RT which is generally delivered to a dose of 66-70Gy is a prolonged treatment of 6-7 weeks.

IGRT is a technique where with the help of CT imaging before RT, attempt is made to identify the movements three dimensionally and efforts are made to correct it.