Tests for thyroid cancer

Usually you begin by seeing your family doctor who will examine you and ask about your general health. Your doctor will ask you about your symptoms. This will include what the symptoms are, when you get them and whether anything you do makes them better or worse. The GP will then examine your neck. You will probably be asked to go for a blood test to check your thyroid hormone levels. If your doctor then feels that further tests are needed, they will refer you to a specialist at your local hospital.

When you see a specialist, they will ask you about your medical history and symptoms. They will then examine you by feeling your neck.

If your GP has not already taken blood for thyroid tests, you will have some blood taken. The laboratory staff will check the blood for your thyroid hormone levels and to see if the blood contains particular proteins called thyroid antibodies. Then they will arrange other tests in the outpatient department. You may be asked to have

• An ultrasound scan
• A needle biopsy

An ultrasound scan uses sound waves to build up a picture of the inside of your body. This test can be used to look at your thyroid and neck. Your doctor is looking to see whether there are lots of lumps or just one. And whether the lumps are solid or filled with fluid (cysts). Of these, a single solid lump is most likely to be cancer. An ultrasound may be used to help find the thyroid lump during a needle biopsy (see below). There is more about having an ultrasound in the cancer tests section of CancerHelp UK.

A needle biopsy is used to take a small amount of thyroid tissue, which can be looked at under a microscope. This is the only way to be sure if a lump is cancer or not.

The doctor will feel for your thyroid lump, so that they can put the needle straight into the right place. Often, they use an ultrasound scanner to help guide the needle in. You may have an injection of local anaesthetic to numb the area. Doctors don't always use anaesthetic because the needle to take the biopsy is very thin. So if you definitely want a local anaesthetic, make sure that you ask. Then the doctor puts the biopsy needle into the lump. Once the needle is in place, the doctor uses it to suck out a small amount of fluid and cells. They send this fluid to the laboratory to be looked at under a microscope. Occasionally the first sample does not contain enough cells to make a definite diagnosis and you may need to have the test again.

Sometimes a surgical biopsy is needed. This could be because

• Needle biopsy could not be done for some reason
• Repeated needle biopsy did not get enough cells to make a diagnosis but your specialist still thinks that there is a problem
• It was difficult for the pathologist to be sure about the results of your needle biopsy (it can be particularly difficult to accurately judge thyroid cells)

You usually have a surgical biopsy under general anaesthetic. The doctor makes a small cut with a scalpel and removes a very small piece of thyroid tissue. You may have one or two stitches, or steristrips, to close the cut in your neck.