Mouth cancer, also known as oral cancer, is where a tumour develops in the lining of the mouth. It may be on the surface of the tongue, the insides of the cheeks, the roof of the mouth (palate), or the lips or gums.
Tumours can also develop in the glands that produce saliva, the tonsils at the back of the mouth, and the part of the throat connecting your mouth to your windpipe (pharynx). However, these are less common.
Symptoms of mouth cancer
Symptoms of mouth cancer ↗ include:
- sore mouth ulcers ↗ that don't heal within several weeks
- unexplained, persistent lumps in the mouth that don't go away
- unexplained, persistent lumps in the neck that don't go away
- unexplained looseness of teeth, or sockets that don't heal after extractions
- unexplained, persistent numbness or an odd feeling on the lip or tongue
- sometimes, white or red patches on the lining of the mouth or tongue – these can be early signs of cancer, so they should also be investigated
- changes in speech, such as a lisp
See your GP or dentist if these symptoms don't heal within three weeks, particularly if you drink or smoke heavily.
Types of mouth cancer
Mouth cancer is categorised by the type of cell the cancer (carcinoma) starts in.
Squamous cell carcinoma is the most common type of mouth cancer, accounting for 9 out of 10 cases.
Squamous cells are found in many places around the body, including the inside of the mouth and the skin.
Less common types of mouth cancer include:
- adenocarcinomas – cancers that develop inside the salivary glands
- sarcomas ↗ – these grow from abnormalities in the bone, cartilage, muscle or other body tissue
- oral malignant melanomas – where the cancer starts in melanocytes, the cells that produce skin pigment; they appear as very dark, mottled swellings that often bleed
- lymphomas – these grow from cells normally found in lymph glands, but can also develop in the mouth
What causes mouth cancer?
Things that increase your risk of developing mouth cancer include:
- smoking or using other forms of tobacco
- drinking alcohol – people who drink and smoke heavily have a much higher risk compared with the population at large
- infection with the human papilloma virus (HPV) ↗ – HPV is the virus that causes genital warts ↗
Read more about the causes of mouth cancer ↗.
Who's affected by mouth cancer?
Mouth cancer is the sixth most common cancer in the world, but it's much less common in the UK.
Around 6,800 people are diagnosed with mouth cancer each year in the UK, which is about 2% of all cancers diagnosed.
Most cases of mouth cancer occur in older adults aged 50 to 74. Only one in eight (12.5%) cases affect people younger than 50.
Mouth cancer can occur in younger adults. HPV infection is thought to be associated with the majority of cases that occur in younger people.
Cancer of the mouth is also more common in men than in women. This may be because, on average, men tend to drink more alcohol than women.
Treating mouth cancer
There are three main treatment options for mouth cancer:
- surgery – where the cancerous cells are surgically removed, along with a tiny bit of the surrounding normal tissue or cells to ensure the cancer is completely removed
- radiotherapy ↗ – where high-energy X-rays ↗ are used to kill cancerous cells
- chemotherapy ↗ – where powerful medications are used to kill cancerous cells
These treatments are often used in combination. For example, surgery may be followed by a course of radiotherapy to help prevent the cancer returning.
As well as trying to cure the cancer, treatment will focus on important functions of the mouth, such as breathing, speaking and eating. Maintaining the appearance of your mouth will also be given high priority.
Read more about treating mouth cancer ↗.
Complications of mouth cancer
Mouth cancer and its treatment can cause a number of complications. It can affect the appearance of your mouth and make speaking and swallowing difficult (dysphagia) ↗.
Dysphagia can be a potentially serious problem. If small pieces of food enter your airways and become lodged in your lungs, it could trigger a chest infection, known as aspiration pneumonia ↗.
Read more about the complications of mouth cancer ↗.
Preventing mouth cancer
The three most effective ways of preventing mouth cancer developing, or preventing it coming back after successful treatment, are:
- not smoking
- ensuring you don't drink more than the recommended weekly limits for alcohol
- eating a healthy, Mediterranean-style diet ↗ that includes plenty of fresh vegetables – particularly tomatoes – and citrus fruits, olive oil and fish
The NHS recommends you drink no more than 14 units of alcohol a week. If you drink as much as 14 units a week, it's best to spread it evenly over three or more days.
It's also important that you have regular dental check-ups ↗ – dentists can often spot the early stages of mouth cancer.
The outlook for mouth cancer can vary depending on which part of the mouth is affected and whether it's spread from the mouth into surrounding tissue. The outlook is better for mouth cancer that affects the lip, tongue or oral cavity.
If mouth cancer is diagnosed early, a complete cure is often possible in up to 90% of cases using surgery alone.
In cases where the cancer is larger, there's still quite a good chance of a cure, but surgery should be followed by radiotherapy or a combination of radiotherapy and chemotherapy to give the best chance.
Advances in surgery, radiotherapy and chemotherapy have resulted in much improved cure rates.
Overall, around 60% of people with mouth cancer will live at least five years after their diagnosis, and many will live much longer without the cancer returning.
Head and neck cancers
Mouth cancer is a type of cancer that comes under the umbrella term, "cancers of the head and neck".
Other types of head and neck cancer ↗ include:
- cancer of the larynx ↗ – the voice box
- cancer of the nasopharynx ↗ – the area at the very back of the nose that forms the top part of the pharynx, or throat
- cancer of the oropharynx – the part of the throat that lies directly behind the mouth
- cancer of the hypopharynx – the part of the throat that lies directly behind the larynx
- cancer of the thyroid gland ↗ – a gland located on either side of the windpipe
- cancer of the nose and sinuses ↗
- cancer of the oesophagus ↗ – the gullet