Diagnosing glucagonoma

You have some tests to diagnose a glucagonoma. This might include blood tests and an endoscopy.

Glucagonoma is a type of neuroendocrine tumour (NET) that starts in the neuroendocrine cells of the pancreas. Glucagonomas make the hormone glucagon, which helps to raise the blood sugar levels in your body. So you might see your GP because of symptoms caused by the increase in the levels of glucagon.

Glucagonomas are rare tumours. 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 a skin doctor (dermatologist) if you have a skin rash.

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

Tests

You have tests to check:

  • whether you have a NET
  • the type of NET you have
  • the size of the tumour
  • 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 your body. You might have an MRI scan to check if the glucagonoma 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.

Endoscopy

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 can tell you which tests you need.
Last reviewed: 
04 Aug 2021
Next review due: 
04 Aug 2024
  • Gastroenteropancreatic neuroendocrine neoplasms: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up
    M. Pavel and others
    Annals of Oncology 2020, Vol 31, Issue 5 

  • Rare Functioning Pancreatic Endocrine Tumors
    D O’Toole and others
    Neuroendocrinology, 2006. Vol 84. Pages 189-195

  • Glucagonoma and the glucagonoma syndrome – cumulative experience with an elusive endocrine tumour
    R Eldor and others
    Clinical Endocrinology, 2011. Vol 74, Pages 593-598

  • ENETS Consensus Guidelines for the Management of Patients with Digestive Neuroendocrine Neoplasms: Functional Pancreatic Endocrine Tumor Syndromes
    R Jensen and others
    Neuroendocrinology, 2012. Vol 95, Pages 98-119

  • Glucagonoma and the glucagonoma syndrome
    Emily Bergsland
    UpToDate, 2021

  • Cancer: Principles and Practice of Oncology (11th edition)
    VT DeVita, TS Lawrence, SA Rosenberg
    Wolters Kluwer, 2019

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