VIPoma causes cells in the pancreas to produce a high level of a hormone called vasoactive intestinal peptide (VIP). This hormone increases secretions from the intestines. It also relaxes some of the smooth muscles in the gastrointestinal system.

The exact cause of VIPomas is not known.

VIPomas are often diagnosed in adults, most commonly around age 50. Women are more likely to be affected than men. This cancer is rare. Each year, only about 1 in 1 million people are diagnosed with a VIPoma.

Symptoms of VIPoma may include any of the following:

• Abdominal pain and cramping
• Diarrhea (watery, and often in large amounts)
• Dehydration
• Flushing or redness of the face
• Muscle cramps due to low blood potassium (hypokalemia)
• Nausea
• Weight loss

Your health care provider will perform a physical exam and ask about your medical history and symptoms.

Tests that may be done include:

• Blood chemistry tests (basic or comprehensive metabolic panel)
• CT scan of the abdomen
• Genetic tests
• MRI of the abdomen
• Stool exam for cause of diarrhea and electrolyte levels
• VIP level in the blood

The first goal of treatment is to correct dehydration. Fluids are often given through a vein (intravenous fluids) to replace fluids lost through diarrhea.

The next goal is to slow the diarrhea. Medicines can help regulate diarrhea. One such medicine is octreotide. It is a manmade form of a natural hormone that blocks the action of VIP.

The best chance of a cure is surgery to remove the tumor. If the tumor has not spread to other organs, surgery can often cure the condition.

You can ease the stress of illness by joining a cancer support group. Sharing with others who have common experiences and problems can help you not feel alone.

Surgery can usually cure VIPomas. But, in one third to one half of people, the tumor has spread by the time of diagnosis and cannot be cured. However, it grows fairly slowly, and its effects often can be regulated by octreotide.

Complications may include:

• Cancer spread (metastases)
• Cardiac arrest from low blood potassium level
• Dehydration

If you have watery diarrhea for more than 2 to 3 days, contact your provider.

Vasoactive intestinal peptide-producing tumor; VIPoma syndrome; Pancreatic endocrine tumor; Verner-Morrison syndrome; WDHA

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De Herder WW, Feelders RA, Hofland J. Neuroendocrine tumors and disorders. In: Melmed S, Auchus RJ, Goldfine AB, Rosen CJ, Kopp PA, eds. Williams Textbook of Endocrinology. 15th ed. Philadelphia, PA: Elsevier; 2025:chap 43.

National Cancer Institute website. Pancreatic neuroendocrine tumors (islet cell tumors) treatment (PDQ) - health professional version. www.cancer.gov/types/pancreatic/hp/pnet-treatment-pdq. Updated August 16, 2024. Accessed October 15, 2024.

Updated by: Sandeep K. Dhaliwal, MD, board-certified in Diabetes, Endocrinology, and Metabolism, Springfield, VA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.