part_of part of part of has_disease_location endocrine gland neoplasm pancreas Pancreatic Vipoma A usually malignant pancreatic neuroendocrine tumor producing vasoactive intestinal peptide (VIP). It is associated with watery diarrhea, hypokalemia, and hypochlorhydria or achlorhydria. One third of cases are metastatic at the time of diagnosis. NCIt:C95599