Normally, cells grow and divide to form new cells in an orderly way. They perform their functions for a while, and then they die. Sometimes, however, cells do not die. Instead, they continue to divide and create new cells that the body does not need. The extra cells form a mass of tissue, called a growth or tumour. There are two types of tumours: benign and malignant. Malignant tumours are cancers in which a group of cells display specific behavior:
These three malignant properties of cancers differentiate them from benign tumours, which are self-limited, and do not invade nearby tissue or spread to other parts of the body.
Most head and neck cancers begin in the cells that line the mucosal surfaces in the head and neck area, such as the mouth, nose, and throat. Mucosal surfaces are moist tissues lining hollow organs and cavities of the body open to the environment. Normal mucosal cells look like scales (squamous) under the microscope, so head and neck cancers originating form these cells are named squamous cell carcinomas. Some head and neck cancers begin in other types of cells. For example, cancers that begin in glandular cells are called adenocarcinomas. Cancers of the head and neck are identified by the area in which they originate:
Oral cavity This includes the lips, the front two-thirds of the tongue, the floor (bottom) of the mouth under the tongue, the gingiva (gums), the buccal mucosa (lining inside the cheeks and lips), the hard palate (bony top of the mouth), and the small area behind the wisdom teeth. Pharynx This is a hollow tube about 12 centremetres long that starts behind the nose and leads to the oesophagus (the tube that goes to the stomach). The pharynx has three parts: nasopharynx (upper part located behind the nose); oropharynx (middle part includes the soft palate (the back of the mouth), the base of the tongue, and the tonsils;) hypopharynx (lower part of the pharynx). Larynx Also called the voice-box, this is located at top of the windpipe (trachea) and in front of the pharynx in the neck. The larynx contains the vocal cords. It also has a small piece of tissue, called the epiglottis, which moves to cover the larynx to prevent food from entering the air passages. Salivary glands These glands produce saliva, the fluid that keeps mucosal surfaces in the mouth and throat moist. There are three pairs of large (major) salivary glands near the jawbone and in the floor of the mouth, and there are hundreds of smaller (minor) salivary glands in the mouth and throat. Paranasal sinuses and nasal cavity Sinuses are small hollow spaces in the bones of the head surrounding the nose. The nasal cavity is the hollow space inside the nose. Cancers of the brain, eye, and thyroid as well as those of the scalp, skin, muscles, and bones of the head and neck are not usually grouped with (mucosal) cancers of the head and neck.
Head and neck cancers have the propensity to spread to lymph nodes in the neck or to the lungs. Rarely they spread to other parts of the body (eg liver, bone, brain). Occasionally squamous carcinoma cancer cells are found in the lymph nodes of the upper neck when there is no evidence of cancer in other parts of the head and neck. When this happens, the cancer is called metastatic squamous neck cancer with unknown (occult) primary.
Head and neck cancers account for approximately 3 to 5 percent of all cancers in New Zealand. These cancers are more common in men and in people over age 50.
Smoking, tobacco or betel nut chewing and heavy alcohol consumption are risk factors for head and neck cancer. However, there is an increasing trend for patients with none of these risk factors and human papillomavirus exposure to develop these cancers.
Symptoms of several head and neck cancer sites include a lump or sore/ulcer that does not heal, a sore throat that does not go away, difficulty breathing, hoarseness or a change in voice change, or difficulty swallowing. Other symptoms may include the following:
Because of the complexity and wide variety of potential diagnoses, your assessment is best performed by a specialist head and neck surgeon who is familiar with the diagnostic possibilities and who is able to assess, recognise and safely take samples (known as biopsies) of abnormalities in the mouth, throat, voice box and sinuses. Your surgeon’s priority is to determine whether or not you have a cancer by performing the following:
Although cancers in the head and neck are relatively rare compared to other cancers occurring in other parts of the body, such as breast, lung and colon, there are many different types of head and neck cancer making correct diagnosis and treatment decisions complex. Many head and neck cancers, if treated correctly, are curable. Your surgeon will want to assess the stage (or extent) of the cancer. Staging is a careful attempt to find out whether the cancer has spread and, if so, to which parts of the body. Staging may involve an examination under anesthesia (in the operating room), biopsy, x-rays, CT scans, and laboratory tests. Knowing the stage of the disease helps the doctor plan treatment.
A multi-disciplinary cancer team assesses all our patients with a new head and neck cancer diagnosis. Dependent on your surgery requirements, you may see a variety of specialist doctors and a specialist support team before your surgery. The team includes head and neck specialist surgeons, nurse specialist, dietitian and swallow and dental specialists, aiming to offer you an expert opinion and treatment choice. Your surgeon is an integral member of the multi-disciplinary head and neck cancer teams based at Mercy Hospital in Epsom, Auckland. The team is internationally recognised for its expertise in treating head and neck cancer patients from all over New Zealand and overseas.
If you are worried about any symptoms, talk to your GP or family doctor and ask for a referral to the MercyAscot Head and Neck Service.