VIPoma: What It Is, How It Causes WDHA Syndrome, and How It Is Treated

A VIPoma is a rare neuroendocrine tumor that secretes vasoactive intestinal peptide (VIP), a hormone that pushes the intestines to release large amounts of water and electrolytes. This excess VIP produces the condition's signature triad, known as WDHA syndrome: watery diarrhea, hypokalemia (low blood potassium), and achlorhydria (little or no stomach acid). VIPomas are diagnosed in roughly one person per 10 million each year, and most are found in the pancreas.

What Is a VIPoma?

A VIPoma is a functional neuroendocrine tumor, meaning it makes a hormone that causes symptoms. It also goes by several other names, including vasoactive intestinal peptide-secreting tumor, Verner-Morrison syndrome, and pancreatic cholera, the last one a nod to the cholera-like diarrhea it triggers.

Around 90% of VIPomas in adults arise in the pancreas, most often in the tail of the gland. In children, these tumors more often start outside the pancreas, in the retroperitoneum or adrenal gland, and may be linked to ganglioneuroma or neuroblastoma.

Vasoactive intestinal peptide tumors are rare, accounting for only about 1% to 2% of pancreatic neuroendocrine tumors. Most measure more than 2 centimeters when they start causing symptoms, and 40% to 60% have already spread to the liver at the time of diagnosis.

WDHA Syndrome: Symptoms of a VIPoma

VIP signals the lining of the gut to secrete fluid rather than absorb it. The result is large-volume, painless, secretory diarrhea that continues even when a person stops eating, which is a key difference from most other causes of chronic diarrhea.

Beyond the classic triad, people may notice flushing, fatigue, muscle cramps, unexplained weight loss, and lightheadedness from dehydration. Some VIPomas also cause high blood calcium or high blood sugar. Severe, untreated cases can lead to kidney failure and dangerous arrhythmias, so symptoms like these deserve prompt medical attention.

What Causes a VIPoma?

The exact vipoma causes are not known, and no diet, smoking habit, or environmental exposure has been proven to raise the risk. Most cases appear to result from acquired mutations in pancreatic neuroendocrine cells rather than an inherited gene.

A minority of VIPomas occur in people with multiple endocrine neoplasia type 1 (MEN1), an inherited syndrome that also predisposes to tumors of the parathyroid, pituitary, and other endocrine glands. Someone diagnosed at a young age, or with a family history of endocrine tumors, is often offered genetic counseling and testing.

How Is a VIPoma Diagnosed?

Diagnosis combines hormone testing, stool studies, and imaging. The single most important lab result is a fasting plasma VIP level, which is typically elevated above 75 pg/mL in people with the tumor. Stool volume stays high during a fast, and the stool osmotic gap is usually below 50 mOsm/kg, both clues that the diarrhea is secretory rather than osmotic.

Blood tests also commonly show low potassium and low bicarbonate, and sometimes an elevated chromogranin A. Gastric acid testing may be used to confirm achlorhydria.

Imaging and Biopsy

CT or MRI of the abdomen is usually the first imaging step. Gallium-68 DOTATATE PET/CT is more sensitive because VIPomas carry somatostatin receptors, and it can reveal small tumors and liver metastases that other scans miss. Endoscopic ultrasound can guide a needle biopsy, which confirms the diagnosis and assigns a tumor grade.

VIPoma Treatment Options

The first priority in vipoma treatment is replacing the fluid, potassium, and bicarbonate the body is losing. Untreated secretory diarrhea can cause life-threatening dehydration within days, so intravenous fluids and electrolyte replacement often begin before the tumor itself is addressed.

Somatostatin analogs such as octreotide and lanreotide are the first-line medications for controlling VIPoma-related diarrhea. They reduce VIP release and slow intestinal secretion, and most patients see relief within a few days.

Surgery offers the only realistic chance of a cure, and it works best when the tumor is confined to the pancreas. When a VIPoma has already spread, care focuses on controlling hormone symptoms and slowing the disease, and many patients receive a combination of the options above.

Outlook and Safety

The outlook for a VIPoma depends mainly on how far the tumor has spread and how aggressive it is under the microscope. People whose tumor is fully removed often live for many years, while metastatic disease shortens survival and requires ongoing care at a neuroendocrine tumor center.

Anyone with persistent watery diarrhea, unexplained low potassium, or signs of dehydration should see a healthcare professional rather than self-treating. Patients often run into unproven peptides and supplements online, and some even search what is bpc-157 made of while looking for gut relief, but no supplement has been shown to treat a VIPoma, and using one instead of medical care can be dangerous. Any change to diet, hydration, or medication should be discussed with the treating team.