All tumors were positive for panendocrine immunohistochemistry markers (chromogranin A and/or synaptophysin); 35% of NETs demonstrated focal positivity for pancreatic polypeptide, somatostatin, insulin, and/or glucagon; and no immunostaining for pancreatic and gastrointestinal hormones was observed in 65% of tumors.
Pancreatic polypeptide update: its roles in detection of the trait for multiple endocrine adenopathy syndrome, type I and pancreatic polypeptide-secreting tumors.
Plasma concentrations of human pancreatic polypeptide constitute an excellent marker system for the detection and assessment of tumor status before and after surgical and streptozocin therapy.
To determine whether this strategy could be used to kill tumor cells without host toxicity, nude mice bearing human malignant D54MG glioma tumors expressing E. coli PNP (D54-PNP) were treated with either 6-methylpurine-2'-deoxyriboside (MeP-dR) or arabinofuranosyl-2-fluoroadenine monophosphate (F-araAMP, fludarabine, a precursor of F-araA).
Ingestion of a standardized test meal for stimulation of gastrin and pancreatic polypeptide could be a complementary procedure for diagnosing gastroenteropancreatic tumors in selected patients with MEN I in whom basal gastrin and pancreatic polypeptide levels are normal.