Clinically silent gross hypergastrinaemia from a multiple hormone-secreting pancreatic apudoma.

A patient is described who had a malignant pancreatic islet cell apudoma secreting corticotrophin (ACTH) and melanocyte-stimulating hormone (MSH), both of which were clinically active, and very large quantities of immunoreactive gastrins, which were biologically active but clinically silent (normal gastric acid secretion and no peptic ulceration). The presence of parietal cell antibodies, with no increase in the plasma concentrations of hormones which can inhibit gastric acid secretion (secretin, GIP and VIP), suggests that many of the of the parietal cells may have been blocked by the autoantibodies.