What is mouth and oropharyngeal cancer

Mouth cancer can start in different parts of the mouth, including the lips, gums or soft sides of the mouth. Oropharyngeal cancer starts in the oropharynx. The oropharynx is the part of the throat (pharynx) just behind the mouth. It includes tonsil cancer and cancer in the back part of the tongue.

This section is about both mouth and oropharyngeal cancer. These cancers often start in the same type of cell. Doctors use similar tests and treatments for these cancers although there are some differences.

If your cancer started on your tongue, you might also find it useful to look at our information about tongue cancer.

You can also find out more about cancer that starts in the tonsils.

The mouth

The medical term for the mouth is the oral cavity. Mouth cancer can start anywhere in the oral cavity. This includes the:

• lips
• inside lining of the cheeks and lips (buccal mucosa)
• front 2/3 of the tongue
• gums (gingiva)
• floor of the mouth
• roof of the mouth (hard palate) 
• area behind the wisdom teeth (retromolar trigone)

The mouth and oropharynx help us breathe, talk, eat, chew and swallow. 

The oropharynx

The medical term for the throat is the pharynx. The pharynx is divided into 3 parts.

The parts are:

• oropharynx
• nasopharynx
• laryngopharynx

The oropharynx is the part of the throat just behind the mouth. Cancer starting in this area is called oropharyngeal cancer (pronounced oar-oh-fah-rin-jee-al).

The oropharynx includes the:

• back 1/3 of the tongue 
• soft area at the back of the roof of the mouth (soft palate)
• tonsils and 2 ridges of tissue in front of and behind the tonsils (tonsillar pillars)
• back wall of the throat

The Human Papilloma Virus (HPV)

Around 70 out of 100 oropharyngeal cancers (around 70%) are linked to the human papilloma virus (HPV). This is a common virus which causes no harm in most people. But in some people, the virus can cause changes in the throat making them more likely to become cancerous in the future. 

The doctors test your oropharyngeal cancer cells to see if they contain the HPV virus. This affects what stage your cancer is and your outlook (prognosis). We know that oropharyngeal cancers containing HPV tend to do better than cancers that don’t contain HPV. At the moment, this doesn't affect your treatment. But doctors are looking at this in research to see if people with HPV positive cancers can have less intense treatments in the future. 

Lymph nodes in your neck

Lymph nodes are small bean shaped glands that are part of the lymphatic system. 

There are major groups of lymph nodes in your neck. Cancers starting in the mouth and oropharynx can spread to these because they are close by. 

Some people with mouth or oropharyngeal cancer often have an operation to remove lymph nodes from the same side of the neck as the cancer. Rarely the surgeon might remove them on both sides. These operations are called neck dissections. 

Cancer that starts in the lymph nodes is called lymphoma. This is very different to a mouth or oropharyngeal cancer that has spread to the lymph nodes. 

What throat cancer means

The term throat cancer can be confusing because people use it to mean different types of cancer. People use the term to include the:

• 3 parts of the pharynx (oropharynx, nasopharynx, laryngopharynx)
• thyroid
• voice box (larynx)
• food pipe (oesophagus)

To avoid confusion, it is important to know the exact type of cancer you have. Cancers are treated according to where they start in the body. Ask your doctor if you do not know the name of the type of throat cancer you have. 

Who gets it

Mouth and oropharyngeal cancer is more common in men than women. 1 in 75 men and 1 in 150 women will be diagnosed with mouth cancer at some point in their life. 

Most mouth and oropharyngeal cancers are diagnosed in people over 60. 

How common it is

Each year around 7,800 new cases of mouth and oropharyngeal cancer are diagnosed in the UK.