NCCN Guidelines for Patients
Thyroid Cancer, Version 1.2017
Imaging tests are used to take pictures (images)
of the inside of your body. Your doctor will want to
check the thyroid and central neck area. Imaging
can be used to see if there is cancer in the body.
These tests can see if the cancer is in more than
one area. Imaging tests may also be done during or
after treatment to see how the body is responding.
Ultrasound is the most common imaging test used
for thyroid cancer.
See Guide 3.
An ultrasound is a test that uses sound waves to
take pictures of the inside of the body. During this
test, you will be asked to lie on a table or sit in a
chair. A hand-held device will be used called an
ultrasound probe. A gel will be put on the skin. The
probe will then be moved back and forth over the
skin. It will send sound waves to tissues and organs.
Echoes will bounce off the tissues and organs, and
is what will form pictures on the screen.
Guide 3. Imaging tests
What is your doctor checking?
high-energy sound waves to make
• Your thyroid, neck, and lymph nodes in that area
Radioiodine scan (also known as RAI imaging or
radiotracer allows a camera to detect if
the thyroid or thyroid cancer cells in the body take up
• Your thyroid
• Your whole body after thyroid surgery to see if any
thyroid cancer cells remain
MRI (magnetic resonance imaging) scan-
waves and strong magnets to make detailed pictures.
• Your neck or other areas of the body like the liver
CT (computed tomography) scan-
x-rays are done to
take pictures from many angles.
• Your neck
• Your chest, abdomen, and pelvis
◦◦ You can get dye (contrast material) for this type
PET (positron emission tomography) scan-
detects disease and takes 3-D pictures.
• How your body is working
• Can be combined with CT scan for more detailed
These pictures will allow your doctors to assess the
size, shape, contents, and place of a nodule. An
ultrasound of the thyroid and neck is not painful. It
usually takes 10 to 30 minutes to complete. A health
professional or your doctor will do the test and review
Although ultrasound is the most common imaging
test, CT scan, PET (
scan, and MRI (
are imaging tests that might be done in certain
situations. A PET/CT (
omography) with a radiotracer called
lucose) is a recommended
imaging test for more aggressive thyroid cancers
such as poorly differentiated cancer or anaplastic
thyroid cancer. FDG is made of fluoride and sugar
(glucose). Cancer cells use more FDG than normal
cells, so they show up as bright spots on the PET
See Guide 3.