Head and neck cancer is a term to describe a number of different malignant tumors that develop in the mouth, nose, sinuses, salivary glands, throat, and lymph nodes in the neck

Most of these cancers are squamous cell carcinomas. Squamous cell cancer begins in the flat cells that make up the thin layer of tissue on the surface of the structures in the head and neck. These cells are called squamous cells. Directly beneath this layer of tissue or lining, which is called the epithelium, some areas of the head and neck have a layer of moist tissue, called the mucosa. If the cancer is found only in the squamous layer of cells, it is called carcinoma in situ. If a cancer has grown beyond this cell layer and has  moved into deeper tissue, then it is called invasive squamous cell carcinoma.

There are five main types of head and neck cancer. Each type is named according to the part of the body where they develop.

• Laryngeal and Hypopharyngeal Cancer. The larynx is commonly called the voice box. It is a tube-shaped organ in the neck that is important for breathing, talking, and swallowing. It is located at the top of the windpipe, or trachea. The hypopharynx is also called the gullet. It is the lower part of the throat that surrounds the larynx.

• Nasal Cavity and Paranasal Sinus Cancer. The nasal cavity is the space just behind the nose where air passes on its way to the throat. The paranasal sinuses are the air-filled areas that surround the nasal cavity.

• Nasopharyngeal Cancer. The nasopharynx is the air passageway at the upper part of the throat behind the nose.

• Oral and Oropharyngeal Cancer. The oral cavity includes the mouth and tongue. The oropharynx includes the middle of the throat from the tonsils to the tip of the voice box.

• Salivary Gland Cancer. The salivary gland is tissue that produces saliva, which is the fluid that is released into the mouth to keep it moist and that contains enzymes that begin breaking down food.

Other types of cancer can also be located in the head and neck region, but the diagnosis and treatment are very different. There are brain tumors, eye cancer, esophageal cancer, thyroid and  parathyroid cancer, and sarcomas.

People with head and neck cancer often experience the following symptoms or signs. Sometimes, people with head and neck cancer do not show any of these symptoms. Or, these symptoms may be caused by a medical condition that is not cancer.

• Swelling or sore that does not heal; this is the most common symptom
• Red or white patch in the mouth
• Lump, bump, or mass in the head or neck area, with or without pain
• Persistent sore throat
• Foul mouth odor not explained by hygiene
• Hoarseness or change in voice
• Nasal obstruction or persistent nasal congestion
• Frequent nose bleeds and/or unusual nasal discharge
• Difficulty breathing
• Double vision
• Numbness or weakness of a body part in the head and neck region
• Pain or difficulty chewing, swallowing, or moving the jaw or tongue
• Ear and/or jaw pain
• Blood in the saliva or phlegm, which is mucus discharged in mouth from respiratory passages
• Loosening of teeth
• Dentures that no longer fit
• Unexplained weight loss
• Fatigue

If you have one or more of these symptoms or signs on this list, please talk with your doctor.