Tests for neuroendocrine tumours (NETs)

You usually start by seeing your GP if you have symptoms. They examine you and might refer you for tests or to a specialist. Some people may be diagnosed with a neuroendocrine tumour during tests for another condition.

You might have a number of tests to help diagnose a neuroendocrine tumour or to see how big the NET is and whether it has spread.

We haven't listed all the tests you might have below. We have more information about tests to diagnose cancer and how you have them in our general cancer tests section.

Urine tests for neuroendocrine tumours (NETs)

Neuroendocrine tumours sometimes release high amounts of serotonin. This breaks down into a substance called 5-HIAA. Your doctor can test for this in your urine.

CT scan for neuroendocrine tumours (NETs)

A CT scan can show up a neuroendocrine tumour (NET) and see whether it has spread anywhere else in your body.

Ultrasound scan for neuroendocrine tumours (NETs)

Ultrasound scans use high frequency sound waves to build up a picture of the inside of the body.

MRI scan for neuroendocrine tumours (NETs)

MRI stands for magnetic resonance imaging. It can use magnetism and radio waves to create cross section pictures of the body.

PET-CT scan for neuroendocrine tumours (NETs)

A PET-CT scan combines a CT scan and a PET scan. You might have a PET-CT scan to find out where the NET is and whether it has spread to other parts of your body. 

Radioactive scans for neuroendocrine tumours (NETs)

You have an injection of a low dose radioactive substance, which can show up on a scan. These scans help to diagnose some neuroendocrine tumours.

Colonoscopy for neuroendocrine tumours (NETs)

A colonoscopy looks at the whole of the inside of your large bowel. Doctors use this test to help diagnose bowel neuroendocrine tumours.

Endoscopy for neuroendocrine tumours (NETs)

An endoscopy is a test that looks inside the body. Doctors use an endoscopy test to help diagnose certain types of neuroendocrine tumours.

Biopsy for neuroendocrine tumours (NETs)

A biopsy means surgically removing a piece of tissue so that a pathologist can look at it under a microscope.

Blood tests for neuroendocrine tumours (NETs)

Blood tests can help to diagnose some types of neuroendocrine tumours. You might also have one to check your general health.

Last reviewed: 
12 Mar 2021
Next review due: 
12 Mar 2024
Json LD: 
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