Diagnosing mouth cancer

If you have any of the possible symptoms of mouth cancer, your GP will carry out a physical examination and ask about your symptoms.

If mouth cancer is suspected, you will be referred to a specialist for further testing. This is usually an oncologist (a doctor who specialises in the treatment of cancer) or an ear, nose and throat (ENT) specialist.

Biopsy

It may be necessary to remove a small sample of affected tissue to check for the presence of cancerous cells. This procedure is known as a biopsy.

There are three main methods used to carry out a biopsy in cases of suspected mouth cancer. They are outlined below.

Punch biopsy

A punch biopsy may be used if the suspected affected area of tissue is in an easily accessible place, such as your tongue or the inside of your mouth.

The area is first injected with a local anaesthetic to numb it. The doctor will then cut away a small section of affected tissue and remove it with tweezers.

The procedure is not painful, but can feel a little uncomfortable.

Fine needle aspiration (FNA)

A fine needle aspiration (FNA) is a type of biopsy used if it is suspected a swelling in your neck is the result of mouth cancer.

During a FNA, the doctor will insert a sharp needle into the lump and draw out a small sample of tissue and fluids. The sample is then checked for cancerous cells.

Local anaesthetic is used to numb your neck, so an FNA is not painful. However, it can be uncomfortable and you may have bruising after the procedure.

Panendoscopy

A panendoscopy is a procedure used to obtain a biopsy when the suspected tissue is at the back of your throat or inside one of your nasal cavities.

The doctor uses an instrument called a panendoscope. This is a long thin tube that contains a camera and light source. The panendoscope is guided through your nose, then used to remove a small section of tissue for the biopsy.

The panendoscope can also check whether cancer has spread from your mouth to further down your throat, such as your larynx (voice box), oesophagus (gullet) or trachea (windpipe).

Further tests

If the biopsy shows the presence of cancer, further testing will be required to check how advanced it is and how far it has spread. This is known as the stage of the cancer.

Cancer spreads from the site of the initial tumour into the lymphatic system. The lymphatic system is a series of vessels and glands (or nodes) spread throughout your body, much like your blood circulation system. These glands produce many of the specialised cells needed by your immune system.

Once the cancer reaches the lymphatic system, it is capable of spreading to any other part of your body, including your bones, blood and organs. It is uncommon for mouth cancer to spread further than the surrounding lymph nodes, although in some cases it may also spread to surrounding bones, such as the jaw bone, and in some cases your lungs.

Therefore, the tests will examine your lymph nodes, bones and the tissue near the site of your initial tumour to check for the presence of other tumours.

The tests that may be used include:

• an X-ray
• a magnetic resonance imaging (MRI) scan
• a computerised tomography (CT) scan
• a positron emission tomography (PET) scan

A PET scan involves injecting a part of your body with a radioactive ‘tracer’ chemical that can be seen on a special camera.

Further biopsies on nearby lymph nodes may also be carried out.

Staging and grading

Once these tests have been completed it should be possible to tell what stage and grade your cancer is:

• staging is a measure of how far the cancer has spread
• the grade is an assessment of how aggressive the cancer is and how fast it is likely to spread in future

This will help determine whether you have:

• early mouth cancer (usually curable)
• intermediate mouth cancer (may be curable)
• or advanced mouth cancer (not usually curable, but it is usually possible to slow the spread of the cancer and extend lifespan)

There are three grades of mouth cancer:

• low-grade – where the cancer spreads slowly
• moderate-grade – where the cancer spreads at a medium pace
• high-grade – where the cancer is very aggressive and likely to spread quickly if untreated

The grading of your cancer can often determine whether you require immediate treatment or whether treatment can be safely delayed for a period of time – read more about treating mouth cancer.