Cancer of the tongue, mouth and pharynx is much more common in India, Bangladesh, Sri Lanka, Thailand and Indonesia than in other countries. It accounts as much as 30 to 50 per cent of all cancers in India. In the Western countries, it accounts for only 3 to 5 per cent of all cancers.

Causes

Approximately 90 per cent of oral cancers in India can be attributed to tobacco chewing and also smoking. These cancers almost always occur on the side of the mouth where the tobacco quid is kept, and the risk of cancer rises drastically for those who keep the tobacco quid in the mouth over­ night. A link also seems to exist between infection with HSV (Herpes simplex virus) and oral cancer.

Symptoms

Onset of the cancer at this site is usually preceded by the inner lining of the lip turning into a white patch on which a hard mass slowly develops the top of which some times becomes an ulcer.

Cancer of the lower lip is generally caused by the habit of depositing khaini, a mixture of tobacco and lime under the lower lip from where it is chewed slowly.

Cancer of the cheek appears as a hard thickening which is painless. Sometimes an ulcer forms over it. If a painless swelling or an ulcer with a hard base forms and does not heal up in about two weeks one must consult a competent doctor to rule out cancer.

Chewing or smoking tobacco and the chronic irritation caused by irregular teeth have been suspected to lead to cancer at this site. Cancer of the tongue involves the back of the tongue and at this site grows unnoticed for many months. It then involves lymph glands in the neck which become enlarged and sometimes it is for them that the patient seeks medical advice. This is generally seen more often in men.

Diagnosis

Rbutine: Physical examination of the local part provides a suspicion.
Blood: Hb, RBC, TLC, DLC, may be normal. ESR may be raised.
Special: Biopsy examination of the involved part confirms the diagnosis.

Treatment

Surgery: Excision of the involved part, the surrounding areas and the lymph nodes, if involved.
Radiation: It is given when suspicion of spread is present, and the whole of the involved area has not been removed through surgery.
Chemotherapy: It is not of much use.

Prognosis

Presently, more than 50 percent of oral cancers are detected only after they have reached an advanced stage. Such cancers are disfiguring and painful, the treatment required is both extensive and expensive, and survival rates are low, with less than one-tenth of the patients surviving 5 years.

Surgery and radiotherapy can cure only the early cancers.