Symptoms and diagnosis of thyroid cancer


Symptoms may be vague at first because thyroid cancer grows very slowly. The symptoms can include:

  • A painless lump in your neck, which gradually gets bigger
  • Difficulty in swallowing or breathing
  • Changes to your voice, including hoarseness

Even though these symptoms can be caused by complaints other than cancer, do have them checked by your doctor.


Testing for thyroid cancer when you have no symptoms is called screening. There is no national screening programme for thyroid cancer at present. Talk to your GP if you think you are at risk.


First visit your family doctor (GP) if you are worried about any symptoms. If your doctor has concerns about you, he or she will refer you to a hospital. There you will see a specialist who may arrange more tests. You may need some of the following tests

  • Fine-needle aspiration or biopsy
  • Surgical biopsy

Fine-needle aspiration: For this test, a small needle is passed gently into the swelling in your neck to take samples of the cells. The cells are then examined under the microscope. Sometimes an ultrasound scanner is used to guide the needle to the right place.

Surgical biopsy: For this test, your doctor will make a small cut in your skin close to your thyroid. You may be given a local anaesthetic to numb the area first. Your doctor will then remove a small sample of your thyroid gland. You may have a surgical biopsy if it is not possible to do a needle aspiration or if your doctor could not collect enough cells.

Other tests:

  • Blood tests
  • CT scan
  • MRI scan
  • PET scan
  • Ultrasound scan

Learn more about the above tests

Special tests

Thyroid radioisotope scan: For this test, a small amount of a slightly radioactive liquid (iodine or technetium) is injected into a vein in your arm. After 20 minutes, you lie on a couch and a machine called a gamma camera is placed over your neck. Cancer cells do not usually absorb the radioactive liquid as well as normal thyroid cells. As a result, the camera can show up any areas of cancer in your thyroid. These are called cold areas or cold nodules.

For more information please read our booklet, 'Understanding Cancer of the Thyroid (pdf, 2.5MB)'.

Call our National Cancer Helpline

Freephone 1800 200 700 to talk to a specialist cancer nurse
It's open Monday-Thursday from 9am to 7pm and Friday from 9am to 5pm