VIPoma: A rare cause of a pancreatic mass

Vasoactive intestinal polypeptide secreting tumor (VIPoma) is a rare neuroendocrine tumor belonging to a group of cancers called pancreatic endocrine tumors (PETs). The incidence is 1 in 10 million. It has previously been described as Verner-Morrison syndrome, watery diarrhea, hypokalemia, and achlorhydria (WDHA) and pancreatic cholera. Patients usually present with chronic diarrhea and are diagnosed late because it is slow growing. Imaging of VIPomas when they are small is difficult and they are easily missed. A 34-year-old man with a 7-year history of diarrhea who had a normal abdominal ultrasound early in the course of his disease but was subsequently found to have a mass in the pancreas 4 years later, is presented.