Diagnosing VIPoma

You have some tests to diagnose a VIPoma. This might include blood tests and scans.

VIPoma is a type of neuroendocrine tumour (NET) that usually starts in the neuroendocrine cells of the pancreas. VIPomas make too much of a hormone called vasoactive intestinal peptide (VIP) which relaxes the muscles of the stomach and bowel. So you might see your GP because of symptoms caused by the increase in the levels of VIP.

VIPomas are rare cancers. So your doctor might ask you to have tests that check for other conditions first.

Seeing your GP

You usually start by seeing your GP. They will ask you about your general health, symptoms and may also examine you. 

Your GP might check your blood pressure, heart rate and temperature. They may arrange for you to have blood tests. Your doctor will then decide if you need to see a specialist.

Referral to a specialist

Your GP looks at your symptoms and decides what specialist to refer you to. For example, they might refer you to the gastrointestinal team (GI) if you have tummy pain or diarrhoea.

The specialist might ask you to have more tests. If tests show that you have a neuroendocrine tumour, your specialist will refer you to a team of doctors and specialist nurses who have expertise in treating NETs.


You have tests to check whether you have a NET, the type of NET you have, the size of the tumour and whether it has spread. This helps your doctor plan your treatment.

Blood tests

Blood tests can check your general health. They can also check the levels of certain substances in the blood which are sometimes raised with NETs. 

You may also have a blood test to check for a rare inherited condition called multiple endocrine neoplasia 1 (MEN1). This test is usually only requested by specialist doctors (genetic doctors). 

CT scan

A CT scan can show up a NET and see whether it has spread anywhere else in the body.

MRI scan

An MRI scan takes detailed pictures of the body. You might have an MRI scan to check if the VIPoma has spread to other parts of the body such as the liver and lymph nodes.

Radioactive scans

These are octreotide scans (or octreoscans) or gallium PET scans. You have an injection of a low dose radioactive substance, which is taken up by some NET cells. The cells then show up on the scan.


This test looks at the inside of your food pipe, stomach and bowel. Your doctor uses a long flexible tube which has a tiny camera and a light on the end of it. Doctors can take samples of any abnormal areas (biopsies).

Endoscopic ultrasound scan (EUS)

This test combines an ultrasound and endoscopy to look at the inside of your food pipe, stomach, pancreas and bile ducts. 

Your doctor uses a long flexible tube (endoscope) with a tiny camera and light on the end. It also has an ultrasound probe. The ultrasound helps the doctor find areas that might be cancer. They then can take samples (biopsies) of any abnormal areas.

You may have other tests depending on your symptoms. Your doctor will tell you which tests you need.
Last reviewed: 
31 Aug 2021
Next review due: 
31 Aug 2024
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    Suayib Yalcin and Kjell Oberg
    Springer, 2015

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    VT DeVita, TS Lawrence, SA Rosenberg
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    Emily Bergsland
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