Ectopic apudocarcinomas and associated endocrine hyperplasias of the foregut.

Foregut endocrine polypeptide-secreting APUD cells (Amine-Precursor-Uptake and Decarboxylation), in their embryologic migration from neural crest to foregut may become "arrested" in the mesoderm or in other ectopic locations. They may become hyperplastic, adenomatous or malignant. Eight illustrative patients are reported. One patient had "pancreatic hyperparathyroidism" with hypercalcemic crises, pancreatic apudocarcinoma, normal parathyroids, biologically active parathormone, but inert immunochemically to the usual parathyroid antisera. Two had gastrin-secreting malignancies in the mesoderm. Remission after excision, but eventual recurrence of the syndrome due to islet cell hyperplasia required total gastrectomy. One patient had a gastric corpus apudocarcinoma found prospectively with hypergastrinemia which required excision of the tumor. One patient had acromegaly with hypergastrinemia and antral gastrinosis treated by pituitary irradiation, One patient had the antral or intermediary type of the Zollinger-Ellison syndrome with moderate hypergastrinemia, duodenal ulcer and antral gastrinosis, treated by vagotomy and antrectomy. One patient had hyperparathyroidism with antral gastrinosis, treated by parathyroidectomy. One patient had malignant Zollinger-Ellison syndrome and developed associated thyroid parafollicular cell hyperplasia and parathyroid chief cell hyperplasia, treated by total gastrectomy and multiple endocrine excisions. These investigative observations demonstrate ectopic loci and associated hyperplasias which support the concept of migration and bizarre potentiality of polypeptide-secreting cells of the foregut.