How thyroid cancer is diagnosed

If you have symptoms, you will usually start by seeing your GP, who will examine you. If they are unsure what the problem is, or think your symptoms could be caused by cancer, they will refer you to a hospital for specialist advice and treatment. You should be seen at the hospital within two weeks.

At the hospital

The doctor will ask you about your general health, family history and any previous medical problems you have had. They will examine you. You may have some of the following tests.

Blood tests

It is not possible to diagnose thyroid cancer through a blood test. But you may have blood tests to check your thyroid function and general health.

Ultrasound thyroid scan

An ultrasound scan uses sound-waves to build up a picture of the inside of the neck and the thyroid gland. Your doctor will also check the lymph nodes in your neck to see if any of them are abnormal. This is because sometimes thyroid cancer can spread to the lymph nodes.

You will be asked to lie on your back for the scan. Once you are lying comfortably, the person doing the scan spreads a gel over your neck. Then they move a small hand-held device like a microphone around your neck area. A picture of the inside of your neck shows up on a screen. An ultrasound only takes a few minutes and is painless.

Fine needle aspiration (FNA)

A doctor gently passes a small needle into the lump or swelling in your neck. You may have a local anaesthetic to numb the area. Sometimes the doctor uses an ultrasound scanner to help guide the needle to the right area. Then they take a small sample of cells and examine it under a microscope to check whether there are any abnormal cells.

If an FNA does not collect enough cells, sometimes it is done again.

Core biopsy

Very occasionally you may need to have a core biopsy. You have a local anaesthetic to numb the area. Sometimes a general anaesthetic is used. Your doctor uses a needle to take a sample of tissue. The needle is slightly bigger than the one they use for the FNA. They may use an ultrasound scanner to guide the needle to the right area. You may have a core biopsy if:

  • the FNA doesn’t collect enough cells
  • the doctor who looks at the cells from the FNA under the microscope (pathologist) is not sure whether there are cancer cells present.

If you need to have surgery to remove all or part of your thyroid gland, your doctor may suggest you have the surgery straight away rather than having a core biopsy.

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