Further tests for thyroid cancer
The specialist may want to do some further tests to find out the size and position of the cancer, and whether it has spread to other parts of the body.
These may include any of the following:
MRI (magnetic resonance imaging) scan
This test uses magnetism to build up a detailed picture of areas of your body. The scanner is a powerful magnet, so you may be asked to complete and sign a checklist to make sure it’s safe for you. The checklist asks about any metal implants you may have, such as a pacemaker, surgical clips or bone pins.
You should also tell your doctor if you’ve ever worked with metal or in the metal industry, as very tiny fragments of metal can sometimes lodge in the body. If you do have any metal in your body, it’s likely that you won’t be able to have an MRI scan. In this situation another type of scan can be used.
Before the scan, you’ll be asked to remove any metal belongings including jewellery. Some people are given an injection of dye into a vein in the arm, which doesn’t usually cause discomfort. This is called a contrast medium and can help the images from the scan to show up more clearly.
During the test, you’ll lie very still on a couch inside a long cylinder (tube) for about 30 minutes. It’s painless but can be slightly uncomfortable, and some people feel a bit claustrophobic. It’s also noisy, but you’ll be given earplugs or headphones. You can hear, and speak to, the person operating the scanner.
CT (computerised tomography) scan
A CT scan takes a series of x-rays, which build up a three-dimensional picture of the inside of the body. The scan takes 10–30 minutes and is painless. It uses a small amount of radiation, which is very unlikely to harm you and will not harm anyone you come into contact with. You will be asked not to eat or drink for at least four hours before the scan.
Someone having a CT scan.
View a large version of this image.
You may be given a drink or injection of a dye, which allows particular areas to be seen more clearly. This may make you feel hot all over for a few minutes.
You’ll probably be able to go home as soon as the scan is over.
PET (positron emission tomography) scan
PET scans can be used to accurately define the cancer and find out if it has spread to other parts of the body. PET scans can also be used to examine any lumps that remain after treatment to see if they are scar tissue or whether cancer cells are still present.
A PET scan uses low-dose radioactive glucose (a type of sugar) to measure the activity of cells in different parts of the body.
It may help to find out whether a tumour is growing and whether it is cancerous (malignant) or non-cancerous (benign).
Vocal cord check
Your doctor may want to check your vocal cords before and after your operation. This is because the nerves that control your vocal cords are close to the thyroid gland.
The surgeon will pass a thin, flexible tube with a small camera at the end, through your nose to look at how your vocal cords move.