Pancreatic polypeptide hyperplasia causing watery diarrhea syndrome: a case report.

Neuroendocrine tumours of the pancreas can secrete numerous peptides, leading to various recognizable clinical syndromes. The secretion of pancreatic polypeptide has been used as a marker for neuroendocrine tumours but is considered to be a biologically inert peptide. A 37-year-old woman had watery diarrhea syndrome from pancreatic polypeptide hyperplasia. Only 2 other reported cases in the literature have described pancreatic polypeptide hyperplasia; however, this is the first reported case in which the patient was successfully treated by surgical resection, with a 2-year follow-up. This report and review of the literature illustrate that pancreatic polypeptide hypersecretion may present as a clinical endocrinopathy.