Pharyngeal cancer arises in the pharynx (throat), the hollow tube inside the neck that starts behind the nose and ends at the top of the esophagus. Tumors in this region include cancer of the nasopharynx (the upper part of the throat behind the nose), the oropharynx (the middle part of the pharynx), and the hypopharynx (the bottom part of the pharynx).
The nasopharynx, located behind the nose, includes two openings that lead to the ears. Nasopharyngeal cancer is much more common in Asia, especially southeast China, the Mediterranean area, and Africa than in the US, and is less commonly associated with tobacco and alcohol use than other head and neck cancers. Risk factors for this type of cancer include a diet high in salt-cured fish and infection with Epstein-Barr virus, a member of the herpesvirus family and one of the most common human viruses. The most common sign of nasopharyngeal cancer is a lump in the neck, caused by the spread of cancer to the lymph nodes. Other symptoms may include nasal congestion, pain or ringing in the ears, a persistent sore throat, or frequent nosebleeds.
The oropharynx is located behind the mouth and includes the base of the tongue, the soft palate (the soft area just beyond the roof of the mouth), and the area around the tonsils. Smoking and chewing tobacco and heavy alcohol use are the most common risk factors for oropharyngeal cancer, but there is evidence that a diet low in fruits and vegetables is clearly linked to this form of head and neck cancer. Prior infection with human papillomavirus (HPV) is also a particularly strong risk factor for this cancer site. Symptoms of oropharyngeal cancer may include a lump in the neck or throat, persistent sore throat, hoarseness, difficulty swallowing, and ear and/or jaw pain.
The hypopharynx is the uppermost portion of the esophagus (the tube through which food travels to the stomach) and surrounds the larynx (voice box). As with most other head and neck cancers, tobacco use and heavy alcohol consumption are the most common risk factors. Other risk factors for hypopharyngeal cancer may include a diet low in vitamins A and E; exposure in the work place to asbestos, wood dust, paint fumes, and other inhalants; and Plummer-Vinson syndrome (a rare condition that causes difficulty swallowing). Symptoms of hypopharyngeal cancer may include a lump in the neck, hoarseness, difficulty swallowing, and ear pain.