Mouth cancer

Mouth cancer is also known as oral cancer. It is one of the most common types of head and neck cancer. It can start in any part of the mouth.

The mouth

The mouth may also be called the oral cavity. It includes the:

• lips
• front part of the tongue, called the oral tongue
• floor of the mouth, under the tongue
• inside the cheek
• roof of the mouth, called the hard palate
• area behind the wisdom teeth
• upper and lower gums.

The most common places for mouth cancer to develop are on the side of the tongue and the floor of the mouth.

The main causes of mouth cancer are:

• smoking or chewing tobacco
• drinking large amounts of alcohol.

Your risk of developing mouth cancer is higher if you do both.

Other things that may increase your risk of mouth cancer are:

• chewing betel quid (paan), gutkha or pan masala (even if it does not have tobacco in it)
• having medical problems that cause a weak immune system
• eating an unhealthy diet without enough fresh fruit and vegetables
• long-term ultraviolet light exposure (from sunlight, sunbeds or sunlamps), which increases the risk of lip cancer.

Having one or more risk factors does not mean you will get mouth cancer. Also, having no risk factors does not mean you will not develop mouth cancer.

The results of your tests helps your doctors find out more about the size, depth and position of the cancer and whether it has spread. This is called staging.

The grade of the cancer describes how the cancer cells look under the microscope. This gives an idea of how quickly the cancer might develop.

Knowing the grade and stage helps your doctors plan the best treatment for you.

The most commonly used staging systems for mouth cancer are the TNM and number staging systems.

TNM staging system

TNM stands for tumour, node and metastases.

Tumour (T)

T describes the size of the tumour and whether it has grown into the surrounding areas. It is numbered 0 and 4 depending on the size and extent of the tumour.

• T0 means there are no signs of a tumour in the mouth, but there may be abnormal cells that are pre-cancerous.
• T1 the tumour is smaller than 2cm and less than 5mm deep.
• T2 the tumour may be smaller than 2cm and deeper than 5mm but not deeper than 10mm. Or, tumours may be larger than 2cm but less than 4cm and not deeper than 10mm.
• T3 the tumour may be larger than 2cm but less than 4cm and are deeper than 10mm. Or, tumours may be larger than 4cm but not deeper than 10mm.
• T4 the tumour may be larger than 4cm and deeper than 10mm. Or, the tumour may have spread into nearby areas, such as muscles or bones.

Nodes (N)

Nodes describes whether the cancer has spread to the lymph nodes.

Metastases (M)

M describes whether the cancer has spread to another part of the body (called metastatic cancer).

The number staging system combines all the information from TNM staging and gives it a number from 1 to 4.

Read more about this in our information about staging and grading of head and neck cancer.

Grading of mouth cancer

A doctor looks at a sample of the cancer cells under a microscope to find out the grade of the cancer.

• Grade 1 or low grade – the cancer cells look like normal cells and usually grow slowly.
• Grade 2 and 3 – the cancer cells look different to normal cells and are slightly faster growing.

You have regular follow-up appointments after treatment. You may also have regular follow-up appointments with your multidisciplinary team (MDT), including,a speech and language therapist (SLT), dietitian, restorative dentist and dental hygienist and sometimes a physiotherapist.

If you have any problems or notice new symptoms between appointments, let your doctor or nurse know as soon as possible.

Some treatment side effects may take a long time to improve after treatment finishes, or they may become permanent. These are called long-term effects. Other side effects can develop months or even years after treatment has finished. These are known as late effects. We have more information about long-term and long-term and late effects of head and neck cancer treatment.

Head and neck cancer and its treatment can sometimes have an effect on your sex life.

If you are worried about this, talk to your doctor or nurse. You can read about things that may help in our information on cancer and sex.

Some cancer treatments can also affect whether you can get pregnant or make someone pregnant. If you are worried about this, it is important to talk with your doctor before you start treatment.

We have more information about:

• fertility in women after treatment
• fertility in men after treatment.
• LGBTQ+ people and cancer treatment

Even if you already have a healthy lifestyle, you may choose to make some positive lifestyle changes during and after treatment. For example, if you smoke or drink alcohol, it is best to avoid smoking or reduce the amount of alcohol.

Eating well and keeping active can improve your health and well-being. It can also help your body recover. Your dietitian can help with any difficulties you might have with eating after treatment.

It may take several months to recover from treatment. It can be hard if treatment has changed your appearance, how you eat or drink, or your voice. This may also affect your body image but there are ways to help you to manage any changes.

You may still be coping with difficult feelings. Talking to your family and friends or health professionals about how you feel can help them know how to support your well-being.

There are also national support groups that you may find helpful:

• The Mouth Cancer Foundation
  The Mouth Cancer Foundation gives information and support to people affected by head and neck cancers.
• Changing Faces
  Changing Faces offers advice and information to anyone who is affected by a change in their appearance.
• The Swallows Head and Neck Cancer Support Group
  The Swallows offers a 24-hour support line to anyone affected by head and neck cancer.
• Salivary Gland Cancer UK
  Salivary Gland Cancer UK supports people with rare salivary gland cancers, such as adenoid cystic carcinoma, ACC, and unknown carcinoma.

Macmillan is also here to support you. If you would like to talk, you can:

• Call the Macmillan Support Line on 0808 808 00 00.
• Chat to our specialists online.
• Visit our head and neck cancer forum to talk with people who have been affected by head and neck cancer, share your experience, and ask an expert your questions.