Vasoactive intestinal polypeptide and gastrin-producing islet cell carcinoma.

A 61-year-old woman had watery diarrhea, hypochlorhydria, hypokalemia, and elevated serum gastrin levels. She had islet cell carcinoma of the body of the pancreas with multiple metastases to the liver. Radioimmunoassay and immunofluorescence demonstrated both vasoactive intestinal polypeptide (VIP) and gastrin in the surgically removed carcinoma and in a metastatic focus. Electron microscopical findings confirmed the presence of two cell types whose secretory granules had characteristics ascribed to these two hormones. Plasma prostaglandin E levels were also elevated above normal. Serum VIP levels became elevated to the Verner-Morrison range prior to her death of a bleeding duodenal ulcer two years after initial symptoms.