Thyroid cancer
Diagnosis and tests
Diagnosing thyroid cancer
Your family doctor (GP) will talk to you about your symptoms. They may do some tests. For example, feeling your throat or blood tests.
Your GP will refer you to hospital if they think you need more tests. Tests you might have include:
A needle is passed 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.
Your doctor will remove a small sample of your thyroid gland under local anaesthetic through a small cut in your skin. The cells are looked at under a microscope in the lab to see if there are any cancer cells.
A device like a microphone passed over your throat to check the size and shape of your thyroid and if any lumps are present. Read more about ultrasound scans.
Blood tests can check your thyroid hormone levels. For example, the levels of thyroid-stimulating hormone (TSH) in your blood. This can tell if your thyroid gland is not working well. Calcitonin is a hormone produced by medullary thyroid cancers that can be measured in the blood as well. The level of calcium in your blood will also be checked.
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. Nodules that have cancer cells do not usually absorb the radioactive liquid as well as normal thyroid cells. As a result, it can show if the nodules are overactive (hot) or underactive (cold).
An endocrinologist is a doctor who specialises in treating problems with the thyroid and other glands.
If you are diagnosed with thyroid cancer, we're here for you.
Our cancer nurses are here if you need information or just want to talk. They can help you to understand your diagnosis and what to expect, send you information and tell you about our services.
Further tests for thyroid cancer
You may need further tests to give your doctors more information about your general health and about the cancer. For example:
A scan that uses magnetic energy to build up a picture of the tissues inside your body. During the scan you will lie inside a tunnel-like machine.
Read more about MRI scans.
A type of X-ray that gives a detailed picture of the tissues inside your body.
Read more about CT scans.
A radioactive injection that will show up any cancer spread to other parts of your body on a CT scan picture.
Read more about PET scans.
The tests you have can help to:
- Stage your cancer. This means finding out the size and position of the cancer.
- Grade your cancer. Grading describes how quickly the cancer may grow and spread and how it might respond to treatment.
Some tests may be used see how you are responding to treatment.
Waiting for test results
While some results may come back quickly, others may take a few weeks. Waiting for results can be an anxious time. It may help to talk things over with your doctor or nurse or with a relative or close friend. You can also call our Support Line on 1800 200 700 or visit a Daffodil Centre to speak to a cancer nurse.
What are the stages of thyroid cancer?
Staging means finding out how big the cancer is and if it has spread to other parts of your body. Staging will help your doctor to plan the best treatment for you.
TNM staging system
The staging system normally used is called TNM. This stands for:
Tumour (T) How big is the tumour?
Node (N) Is there cancer in the lymph nodes?
- N0: No lymph nodes are affected.
- N1: Some lymph nodes near where the airways join the lungs are affected.
- N2: Some lymph nodes in the centre of the chest or where the trachea enters the lung are affected.
- N3: Some lymph nodes on the opposite side of your chest to where the tumour is, or near your collarbone, are affected.
Metastasis (M) Has the cancer has spread?
- M0: The cancer has not spread to other parts of the body.
- M1: The cancer has spread to other parts of the body.
Number staging
Your doctor often uses the TNM information to give your cancer a number stage – from 1 to 4. A higher number means a more advanced cancer.
Knowing the stage and grade of your cancer helps your team to plan the best treatment for you.
What are the grades of thyroid cancer?
Grading describes how quickly the cancer may grow and spread.
- Low-grade thyroid cancer: The cancer cells look only slightly abnormal, much like normal thyroid cells. The cancer is usually slow-growing and less likely to spread than high-grade thyroid cancer.
- High-grade thyroid cancer: The cancer cells look fairly or very abnormal and are more likely to grow quickly.
Staging and grading can be hard to understand, so ask your doctor and nurse for more information if you need it.
Continue reading about thyroid cancer
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