Head and neck cancer is a general term used to refer to a range of different cancers that start developing in the head and neck region of the body. This includes the oral cavity, the tongue, palate, jaw, salivary glands, the throat (larynx) and the nose.
Head and neck cancer occurs when malignant tumours grow in any of the tissue or lymph nodes in the head or neck. Not all tumours in the head and neck are malignant.
The head and neck includes the following organs and body parts:
The mouth includes the lips, gums and tongue. The muscles of the base of the tongue (tongue base) continue into the upper throat (oropharynx).
The roof of the mouth is called the hard palate. Behind this is the soft palate. The soft palate lifts to close off the passageways to the nose so food does not go through the nose when swallowing.
Under the tongue and near the upper back teeth are salivary ducts that release saliva into the mouth. These are joined to salivary glands. The major glands are in front of the ears, and under the jaw and tongue. There are hundreds of minor glands in the mouth lining.
The pharynx is a tube that runs from the back of the nose to the gullet (oesophagus) and the windpipe (trachea). The pharynx has three parts: the nasopharynx, oropharynx (including the tonsils) and hypopharynx.
Air passes through the nasopharynx as you breathe in and out. Both food and air pass through the oropharynx and hypopharynx. Food goes into the stomach via the oesophagus, while air goes into the trachea to get to the lungs.
The larynx is a short passageway that connects the lower part of the pharynx (hypopharynx) with the windpipe (trachea). It contains the vocal folds or vocal cords (glottis), which vibrate when air passes through them to produce sound.
Above the vocal folds is a small flap of tissue called the epiglottis, which prevents food going into the trachea when you swallow. Below the vocal folds is the subglottis.
Under the voice box, in front of the trachea, is the thyroid gland.
The nasal cavity is the large, air-filled space behind the nose. The nose and upper respiratory tract warm, moisten and filter the air that you breathe.
Paranasal sinuses are air-filled spaces within your skull that help to lighten the weight of your head. They also produce mucus and vibrate sound when you speak or sing. The sinuses are in four locations: frontal, ethmoid, sphenoid and maxillary.
Most head and neck cancers start in the cells that line the mouth, nose or throat (squamous cells). These are called squamous cell carcinomas. Some cancers start in glandular cells. Many of these are called adenocarcinomas. Squamous cell carcinomas and adenocarcinomas can also occur in other parts of the body.
Mouth or oral cancer – refers to cancer that starts anywhere in the mouth, including the lips, inside cheeks, the front two-thirds of the tongue, floor of the mouth, jaw and the gums.
Salivary gland cancer – refers to cancer that occurs in any of the paired major glands in front of the ears (parotid glands) or beneath the jaw (submandibular glands) or tongue (sublingual glands).
Pharyngeal cancer – refers to cancer that begins in the throat (pharynx): nasopharyngeal, oropharyngeal and hypopharyngeal cancers.
Laryngeal cancer – refers to cancer that starts in the voice box (larynx).
Nasal cancer or paranasal sinus cancer – includes cancer starting in the nose, nasal cavity or the sinuses.
Other cancers in the head and neck area - cancer can start in the tissue of the brain, eye, oesophagus, thyroid gland, skin and scalp. It can also start in the bone or muscle of the head and neck. These cancers are not classified as head and neck cancer. For information about these cancers, call Cancer Council 13 11 20.
About 4000 people in Australia (approximately 2920 men and 1080 women) are diagnosed with head and neck cancer each year.
This includes about 1250 people diagnosed with an oral cancer (mouth and tongue); 900 with lip cancer; 300 with salivary gland cancer; 800 with pharyngeal cancer; 600 with laryngeal cancer; and 150 with nasal or paranasal sinus cancer.
There are many possible symptoms of head and neck cancer. However, displaying these symptoms does not necessarily mean you have cancer. Only a qualified medical practitioner can make this diagnosis.
A number of factors are associated with increased risk.
Smoking and alcohol consumption are the primary risk factors for most types of head and neck cancer, except for salivary gland cancer. Research indicates that at least 75% of head and neck cancers are caused by a combination of cigarette smoking and alcohol consumption.
Tobacco use – Smoking (cigarettes, cigars, pipes) is associated with an increased risk of head and neck cancer, especially cancer of the larynx.
Alcohol use – Alcohol use may lead to an increased risk, especially in heavy drinkers (3 or more drinks a day). Using both tobacco and alcohol magnifies the risk.
Age – Head and neck cancer is most common in people aged 40 years and older.
Sex – In Australia, men are about three times more likely than women to get head and neck cancer.
Viruses – Human papillomavirus (HPV) has been linked to cancers of the oropharynx, and may play a role in other head and neck cancers. Epstein-Barr virus (EBV) may also have a role in the development of some head and neck cancers.
Genetic factors – People from some cultural backgrounds may be more likely to develop types of head and neck cancer. For example, people from southern China and South-East Asia may have an increased risk of nasopharyngeal cancer.
Occupational and environmental exposures – Breathing in asbestos fibres, wood dust, dry-cleaning solvents or certain types of paint or chemicals is associated with an increased risk of laryngeal squamous cell carcinoma.
Oral hygiene – Poor oral health and gum disease have been linked to cancers of the oral cavity.
Sun exposure – Ultraviolet (UV) radiation may cause skin cancer on the lip.
Low immunity – People with low immunity have a higher risk of developing oral and oropharyngeal cancer.
Nutrition – A diet low in fruits and vegetables and Vitamin A increases the risk of oral and oropharyngeal cancer.
Areca nut, betel nut, paan or gutka – Chewing this type of palm tree seed, often wrapped in leaves, may cause oral cancer.
Having one or more of these risk factors does not mean you will get a head and neck cancer. Talk to your doctor if you are concerned about these risk factors.