Further tests for thyroid cancer

This page tells you about tests you may have if you are diagnosed with thyroid cancer. There is information about

A quick guide to what's on this page
Why you need more tests
CT and MRI scans
Thyroid scan
PET scan
After your tests

Further tests for thyroid cancer

If tests show you have thyroid cancer, your specialist will ask you to have further tests to see how big the cancer is and whether it has spread. Further tests will help your doctor to decide which treatment you need. Your doctor will examine your neck and nearby areas to see if there are any enlarged lymph nodes that may contain cancer cells from your thyroid cancer. Further tests may include CT or MRI scans. Sometimes, thyroid scans (using a very small amount of radioactive iodine) or PET scans are used after treatment. They can see if any cancer cells are left.

After the tests

You will be asked to go back to the hospital when your test results have come through. This is bound to take a little time, even if only a day or two. You may feel very anxious during this time. While you are waiting for results it may help to talk to a close friend or relative about how you are feeling. Or you may want to contact a cancer support group to talk to someone who has been through a similar experience.

CR PDF Icon You can view and print the quick guides for all the pages in the Diagnosing thyroid cancer section.

Further tests will help your doctor to decide on the treatment you need. If you have thyroid cancer, your doctor needs to check how large the cancer is and whether it has spread outside the thyroid gland. Your doctor will examine your neck and nearby areas to see if there are any enlarged lymph nodes that may contain cancer cells from your thyroid cancer.

You may have scans of your neck and chest to see if there are any signs of thyroid cancer elsewhere in your body. CT scans can be used to look for cancer anywhere else in the body, especially the lungs. MRI scans can pick up cancer that has spread into the soft tissues, such as in the neck. If you have been diagnosed with medullary thyroid cancer, you may be asked to have a CT or MRI of your abdomen as well.

There is detailed information about having a CT scan and an MRI scan in the cancer tests section of CancerHelp UK.

You may hear this called an isotope scan or a gamma camera scan. It is used sometimes as a follow up test after surgery to remove the thyroid gland. The scan uses a very small amount of radioactive iodine called I131. The iodine is injected into a vein in your arm. You will then be asked to lie on the scanner couch. The gamma camera is put over your neck for a minute or two.

Thyroid cells pick up iodine much more quickly than any other cells in the body. So the iodine collects in your thyroid cells and the radiation can be seen on your scan. Thyroid cancer cells do not pick up iodine as quickly. So they may show up on the scan as areas with no radiation inside the thyroid.

This type of scan may also be used to check whether any cancer cells are left in other parts of the body after radioactive iodine treatment for papillary or follicular thyroid cancer.

The test is painless. The amount of radiation is so very small that it will not harm you. It will not affect anyone else either.

PET scans can show up areas of active cancer cells. They are sometimes used to see if the cancer has come back after treatment if other tests prove negative. You may have to travel to another hospital to have a PET scan, as they are not available in all hospitals in the UK.

You will be asked to go back to the hospital when your test results have come through. This is bound to take a little time, even if only a day or two. You may feel very anxious during this time. At the hospital you will usually have a clinical nurse specialist who can answer any questions and support you. While you are waiting for results it may help to talk to a close friend or relative about how you feel. Or you may want to contact a cancer support group to talk to someone who has been through a similar experience.

You can look for information and support on our thyroid cancer organisations page. You can also find information about counselling services on our counselling organisations page.

If you want to find people to share experiences with on line, you could use CancerChat, our online forum. Or go through MyWavelength. This is a free service that aims to put people with similar medical conditions in touch with each other.