This page tells you about VIPomas, very rare types of tumour that develop in the pancreas. There is information about
VIPomas are tumours that most often develop in the pancreas. They can also rarely start in other organs of the body including the bowel, lung and liver.
VIPoma tumours develop in cells called islet cells, which make hormones in the pancreas. The tumours make the islet cells produce too much of a hormone called vasoactive intestinal peptide or VIP for short. This hormone relaxes the muscles in the stomach and bowel and helps to control the balance of sugar, salt and water within the gastrointestinal tract.
VIPomas are extremely rare, developing in less than 1 in a million people each year in the UK.
Between 4 and 7 out of every 10 VIPomas (40 to 70%) are cancers (malignant) and the rest are benign (non cancerous). VIPomas are usually slow growing and symptoms tend to develop slowly. In people with cancerous tumours the tumour has often spread to another part of the body when it is diagnosed.
VIPomas are a type of neuroendocrine tumour. Neuro means nerve and endocrine means hormone producing. Neuroendocrine tumours (NETs) are tumours that develop in cells that are triggered by nerve cells to produce hormones.
VIPomas are a specific type of gastroenteropancreatic neuroendocrine tumour (GEP NET) or pancreatic neuroendocrine tumour (PNET).
There is a separate question and answer about neuroendocrine tumours.
Symptoms are usually caused by the increase in the amount of the hormone vasoactive intestinal peptide (VIP). They may start slowly and become worse. They include
- Large amounts of watery diarrhoea – needing to go 20 times a day or more
- Muscle weakness, aching and cramps
- Numbness caused by low levels of potassium in the blood (hypokalaemia)
- Dehydration – causing thirst, dry skin, a dry mouth, tiredness, headaches, and dizziness
- Abdominal pain
- Weight loss
If you don’t have treatment for a low potassium level and dehydration it can lead to heart and kidney problems.
This combination of symptoms is sometimes called Verner Morrison syndrome after the doctors who first described it.
The first tests you have are blood tests to check your general health. They include measuring the level of potassium and other minerals in your blood. You will also have a blood test to check the amount of VIP.
Other tests include
Endoscopic ultrasound is an ultrasound scan done from inside your body. You have an endoscopy but the endoscope contains a small ultrasound probe. The ultrasound helps the doctor to find areas that might be cancer. They guide a small needle into the area to remove a sample of cells (a biopsy).
An octreoscan is also sometimes called somatostatin receptor scintigraphy (SSRS). You have an injection of a substance called octreotide and then have a scan using a special type of scanner. Octreotide is taken up by some neuroendocrine tumour cells. Doctors can attach a radioactive substance to the octreotide that shows up on the scan.
The first treatment you have is to replace the fluid, potassium and other minerals you have lost. This means having a drip into your bloodstream. Exactly what you need will depend on how dehydrated you are and on your potassium levels.
You will also have treatment to try to stop the diarrhoea. Drugs called somatostatin analogues, such as octreotide and lanreotide, control diarrhoea in nearly 9 out of 10 people (90%). There is information about somatostatin analogues in the carcinoid section of CancerHelp UK. Carcinoid tumours are another type of neuroendocrine tumour and somatostatin analogues are used to treat them.
Once your symptoms are under control the main treatment is surgery. But surgery is not always possible. Some VIPomas have already spread at the time of diagnosis. If you can’t have surgery to try to cure your VIPoma, you will have treatment to control your symptoms.
The type of surgery you have depends on
- Whether you have one or more tumours
- Where the tumour is
- The size of the tumour
You may have surgery to remove
- Just the tumour
- The head of the pancreas – a pylorus preserving pancreaticoduodenectomy (PPPD)
- The head of the pancreas and part of your stomach – a Whipples operation
- The tail of your pancreas (a distal pancreatectomy)
If the tumour is in your bowel, your surgeon will remove the tumour from the bowel and check for other tumours.
If the tumour is in your lung, your surgeon will remove the tumour from the lung and check for other tumours. You may need just the tumour removed or the tumour and part of the lung.
If your cancer has spread to the liver you may be able to have this tumour removed at the same time. The surgeon may remove just the tumour or part of the liver as well.
Whichever type of surgery you have, if your tumour is cancerous your surgeon will also remove nearby lymph nodes.
These are major operations and there are risks with having this type of surgery. But the aim is to try to cure your VIPoma so you may feel it is worth some risks. You can read more about surgery for tumours in the pancreas, and possible side effects, on the page about surgery to try to cure pancreatic cancer.
Treating symptoms of VIPoma
Some cancerous (malignant) VIPomas are diagnosed when they are already advanced. And some tumours come back after treatment. The most common place for malignant VIPomas to spread to is the liver.
Not everyone with a non cancerous (benign) VIPoma can have surgery. This may be because of other medical conditions or the position of the tumour. If surgery is not possible, you will have treatment to control the amount of acid the tumours produce.
The aim of treatment for VIPomas that can’t be completely removed is to control any symptoms you have rather than cure them. Treatments may include
If the VIPoma has spread and is causing symptoms, you may have surgery to try to control the symptoms by removing some of the tumour. Your doctor will only suggest this if it is possible to remove at least 90% of the tumour. Surgery may include removing tumours in your liver.
As it is major surgery and there are risks, you need to think carefully about the benefits. Will it improve your quality of life enough to make it worth having such a big operation? Your surgeon will talk to you about the risks and benefits and answer any questions you have.
Instead of having a major operation you may be able to have radiofrequency ablation, cryotherapy, or transarterial chemoembolisation (TACE) to reduce your symptoms.
TACE is when you have chemotherapy injected directly into the area of the tumour in the liver. You also have an injection of another substance, which blocks the blood supply to the tumour. This substance may be a gel or tiny plastic beads and helps to keep the chemotherapy around the tumour.
Drugs to control diarrhoea include somatostatin analogues as we have explained above. There is some evidence to suggest that these drugs may also help to control the growth of the VIPoma. If somatostatin analogues aren’t controlling your symptoms, then you may have interferon. Interferon can help to control symptoms in some people.
Research is always more difficult with rare conditions. There are fewer people available to take part in trials, so it takes longer to recruit enough people.
A recent phase 3 trial found that people having everolimus for advanced neuroendocrine tumours (NETs) had a longer time before their cancer started growing again compared to people having a dummy drug (placebo). The average time before the tumour started growing again was 11 months compared to 4.6 months in people having the placebo.
Another phase 3 trial comparing sunitinib with a placebo for advanced NETs found that the average time before the cancer started growing again was 11.4 months compared to 5.5 months in people having the placebo.
The All Wales Medicines Strategy Group (AWMSG) and the Scottish Medicines Consortium recommend that sunitinib and everolimus should be available on the NHS. You should be able to have sunitinib or everolimus if other treatments are not working and you have pancreatic neuroendocrine tumours that cannot be removed with surgery, or have spread to other parts of the body. In England NICE have not looked at these drugs for NET. They may be available through individual funding through your PCT or through the cancer drugs fund if your doctor thinks they may be helpful.
Researchers are also looking into targeted radiotherapy (radio labelled treatment). You may hear this called peptide receptor radioligand therapy (PRRT). This is a way of getting radiotherapy directly to individual tumour cells.
Cells have receptors that particular proteins can attach to. PPRT works in a similar way to an octreoscan. By attaching radiotherapy to proteins that attach to the cancer cell receptors, you can deliver radiotherapy to them. It is too early in the research to know how well this treatment will work for VIPomas.
We need more research to find out which of these new treatments work best and when to use them.
To find out more about neuroendocrine trials go to our clinical trials database and select ‘neuroendocrine tumours’ from the dropdown list.
Coping with a rare condition can be difficult both practically and emotionally. Being well informed about your condition and the possible treatments can make it easier to make decisions and cope with what happens.
It can also help to talk to people with the same condition. But it can be hard to find someone with a rare tumour. Check out Cancer Chat – Cancer Research UK’s discussion forum. It is a place to share experiences, stories and information with other people who know what you are going through.
Question about cancer? Contact our information nurse team