Hormone producing pancreatic islet cell carcinoma: changing clinical presentation.

A patient with pancreatic islet cell carcinoma demonstrated spontaneous remission and recurrence of hyperinsulinism and disappearance of elevated plasma motilin levels. Despite evidence for gastrin production by the tumor initially, the Zollinger-Ellison syndrome was not diagnosed until three years after initial presentation. Diarrhea and steatorrhea could be attributed to hyperchlorhydria rather than to direct intestinal effects of elevated cirulating gastrin, gastric inhibitory peptide or motilin. Pancreatic islet cell carcinomas, considered as a type a APUD cell proliferation, frequently produce more than one hormone; the pattern of hormone secretion may differ with time and clinical manifestations may change accordingly.