Tests to diagnose neuroendocrine cancer
You usually have a number of tests to diagnose cancer. If you have a neuroendocrine cancer, these test results help your doctors find out your type and 
and plan treatment.
The tests include:
- blood tests
- urine tests
- x-rays and scans
- tests to look inside your body - such as
endoscopy or colonoscopy
Tests your GP might do
Most people with symptoms start by seeing their GP. Your GP might do some tests to help them decide if you need to see a specialist. These tests include:
- blood tests
- a physical examination
Your GP may also arrange for you to have other tests. For example, an x-ray or ultrasound scan. You usually have these tests at your local hospital.
Blood tests
There isn't a blood test that will show whether or not you have cancer. But blood tests can check your general health. They can also sometimes pick up problems caused by neuroendocrine cancer. Blood tests can check:
- how well your liver and kidneys are working
- the number of blood cells in your blood such as
platelets and red blood cells - if there is a higher than normal level of
hormones in your blood
Physical examination
Your doctor usually asks you to lie or sit down. They look at and feel your skin and check for any abnormalities or areas that are swollen. Things they look for include signs of bleeding, bruising and infection.
They may also listen to your chest and tummy (abdomen) to find out if they sound normal.
You can ask for someone else to be in the room with you if you want, to act as a chaperone. A chaperone is a trained healthcare professional such as a nurse. A friend or relative can also stay with you for support. They can be with you during the examination.
Tests your specialist might do
Depending on your symptoms and the results of your blood tests, your GP might arrange for you to go to the hospital.
The specialist you see at the hospital depends on your symptoms. For example you might see:
- a
gastroenterologist or gastric surgeon - an endocrinologist who specialises in conditions that affect your hormone system
- a lung specialist
If they suspect neuroendocrine cancer, they refer you to a neuroendocrine .
Your specialist usually repeats the blood tests done by your GP. You also have more tests. These might include:
- further blood tests
- scans such as
CT scan , MRI scan , PET-CT scan and octreoscan - tests to look inside your body - such as endoscopy, bronchoscopy or colonoscopy
- an
endoscopic ultrasound scan to look inside your abdomen
Further blood tests
Your specialist might request further blood tests if you haven't had these done:
Blood tests to check hormone levels
The tests you have depend on where the cancer is and your symptoms.
If your doctor suspects a neuroendocrine cancer they might look at the levels of a specific hormone. These include:
- gastrin
- glucagon
- insulin
- serotonin
- vasoactive intestinal peptide
You mustn't eat before some hormone tests.
For example, if your doctor suspects you have an , you have a long fasting test. This is to check if your blood sugar levels go down if you don’t eat.
Your nurse takes regular blood samples to check your blood sugar. You can drink water but not eat or drink anything else for up to 72 hours. You stay in hospital for this test.
Chromogranin (CgA test)
The chromogranin A (CgA) test measures the amount of CgA in the blood. CgA is a protein that many neuroendocrine cells produce. But CgA can also be raised for other reasons that are not related to cancer. So, the test is not used on its own to diagnose neuroendocrine cancer.
You might have a blood test to check for the level of the protein chromogranin B (CgB) in the blood. This is less common than having a CgA test.
N-terminal pro-brain natriuretic peptide (NT-proBNP) blood test
You might have this blood test, especially if you have carcinoid syndrome. This is one of the tests to check for a complication called carcinoid heart disease.
Checking for multiple endocrine neoplasia 1 (MEN 1)
Specialist doctors ( doctors) might request an extra blood test, This is to check for a rare inherited condition calle. Research shows that people with MEN1 have a higher risk of developing pancreatic NETs.
Urine tests
Neuroendocrine tumours sometimes release high amounts of . This breaks down into a substance called 5-HIAA. Your doctor can test for this in your wee (urine).
A raised amount of 5-HIAA in your urine can be a sign of a neuroendocrine tumour. But it can also be caused by other medical conditions.
You might collect all your urine over 24 hours to measure the amount of 5-HIAA. Or you might be able to give one urine sample. Your nurse or doctor will give you a container to collect your urine in.
For a few days before and during your test, you should avoid eating certain foods that are rich in serotonin. Your hospital team will provide you with a list of what to avoid.
Some medicines can also affect the level of 5-HIAA in your urine. You might need to stop taking them for a few days before your test. Let your doctor or nurse know about any medicines or herbal remedies you are taking.
Tests to look inside your body
The test you have depends on where the suspected neuroendocrine cancer is.
You might have a gastroscopy. This is also called an endoscopy or oesophago gastric duodenoscopy. This is when the doctor passes a thin tube (endoscope) through your mouth. They can look at your stomach and take of any abnormal looking tissue.
For other parts of your body you might have:
- a bronchoscopy - to look inside your lung
- a colonoscopy - to look inside your bowel
Ultrasound scan and endoscopic ultrasound
An ultrasound scan uses high frequency sound waves to create a picture of a part of the inside of your body.
The ultrasound scanner has a probe that gives off sound waves. The probe looks a bit like a microphone. The sonographer presses the probe against your skin. They move it around the area they are scanning.
The sound waves bounce off the organs inside your body, and the probe picks them up. The probe links to a computer that turns the sound waves into a picture on the screen.
You can also have an ultrasound inside your body. You have this during an endoscopy and it is called an .
Taking a sample (biopsy) of the cancer
A biopsy means removing a piece of tissue so that a can look at it under a microscope. This is the only way to be certain if an abnormal area is cancer and what type it is.
You might have a biopsy at the same time as other tests for neuroendocrine cancer. For example, during an endoscopy or ultrasound scan.
How you have a biopsy depends on where your doctor is taking the sample from. Doctors can use scans such as ultrasound or CT scans to help guide many types of biopsies.
CT scan
A CT scan uses x-rays and a computer to create detailed pictures of the inside of your body.
You might have a CT scan of your chest, tummy (abdomen) or pelvis.
MRI scan
MRI stands for magnetic resonance imaging. It uses magnetism and radio waves to create pictures of the inside of body.
MRI scans can sometimes show up soft tissue more clearly than CT scans.
PET-CT scan
A PET-CT scan combines a CT scan and a PET scan. PET stands for positron emission tomography. The PET scan uses a mildly radioactive drug to show up areas of your body where cells are more active than normal.
The CT scan takes a series of x-rays from all around your body. The computer puts them together to create a 3 dimensional (3D) picture.
PET-CT scans can be useful for some types of neuroendocrine cancer. Your doctor will tell you if you need this type of scan.
There are 2 types of PET scans for neuroendocrine cancer:
- FDG PET CT scans assess faster growing neuroendocrine cancers.
- Gallium dotatate PET CT scans are specialised scans. They are only available in a few hospitals. They are to assess neuroendocrine tumours (NETs).
Radioactive scans
Radioactive scans can help your doctors diagnose some types of neuroendocrine cancer. You have an injection of a low dose radioactive substance. This can show up on a scan.
Radioactive scans include:
- octreotide scans (or Octreoscans) – these are also called somatostatin receptor scintigraphy scans
- tektroyd scans
- gallium dotatate PET scans
You might also have an mIBG scan, but this is less common now. mIBG stands for metaiodobenzylguanidine.
Treatment for neuroendocrine cancer
The tests you have help your doctor find out if you have neuroendocrine cancer. And it tells them what type it is, and where it is in your body.
This is important because doctors use this information to recommend the best treatment for you.
Coping with neuroendocrine cancer
Coping with a diagnosis of neuroendocrine cancer can be difficult. There is help and support available for you and your family.
