About Head and Neck Cancers

About Head and Neck Cancers

What are cancers of the head and neck?

Cancers that are known collectively as head and neck cancers usually begin in the squamous cells that line the mucosal surfaces of the head and neck (for example, those inside the mouth, throat, and voice box). These cancers are referred to as squamous cell carcinomas of the head and neck. Head and neck cancers can also begin in the salivary glands, sinuses, or muscles or nerves in the head and neck, but these types of cancer are much less common than squamous cell carcinomas (1, 2).

Cancers of the head and neck can form in the: 

Oral cavity: Includes the lips, the front two-thirds of the tongue, the gums, the lining inside the cheeks and lips, the floor (bottom) of the mouth under the tongue, the hard palate (bony top of the mouth), and the small area of the gum behind the wisdom teeth.

Throat (pharynx): The pharynx is a hollow tube about 5 inches long that starts behind the nose and leads to the esophagus. It has three parts: the nasopharynx (the upper part of the pharynx, behind the nose); the oropharynx (the middle part of the pharynx, including the soft palate [the back of the mouth], the base of the tongue, and the tonsils); the hypopharynx (the lower part of the pharynx).

Voice box (larynx): The voice box is a short passageway formed by cartilage just below the pharynx in the neck. The voice box contains the vocal cords. It also has a small piece of tissue, called the epiglottis, which moves to cover the voice box to prevent food from entering the air passages.

Paranasal sinuses and nasal cavity: The paranasal sinuses are small hollow spaces in the bones of the head surrounding the nose. The nasal cavity is the hollow space inside the nose.

Salivary glands: The major salivary glands are in the floor of the mouth and near the jawbone. The salivary glands produce saliva. Minor salivary glands are located throughout the mucous membranes of the mouth and throat.

 

Head and neck cancer regions. Illustrates location of paranasal sinuses, nasal cavity, oral cavity, tongue, salivary glands, larynx, and pharynx (including the nasopharynx, oropharynx, and hypopharynx).

Credit: © Terese Winslow

Cancers of the brain, the eye, the esophagus, the thyroid gland, and the skin of the head and neck are not usually classified as head and neck cancers.

If a squamous cell carcinoma of the head and neck is going to spread, it almost always does so locally and/or to the lymph nodes in the neck. Sometimes, cancerous squamous cells can be found in the lymph nodes of the upper neck when there is no evidence of cancer in other parts of the head and neck, possibly because the original primary tumor is too small. When this happens, the cancer is called metastatic squamous cell carcinoma with unknown (occult) primary. More information about this cancer type can be found in the Metastatic Squamous Neck Cancer with Occult Primary (PDQ®) cancer treatment summary.