Role of peptide radioimmunoassay in understanding peptide-peptide interactions and clinical expression of gastroenteropancreatic endocrine tumors.

Peptide radioimmunoassay has become an important clinical and research tool in understanding the role of peptides in the pathophysiology of gut endocrine tumor syndromes. A gut peptide radioimmunoassay laboratory has been established for the diagnosis and clinical monitoring of endocrine tumors of the gastroenteropancreatic (GEP) system. Radioimmunoassay has enhanced our awareness that co-occurring peptide interactions may modify and ultimately influence the clinical expression of these tumors. Furthermore, it has helped develop a rationale for the use of prototype peptides such as somatostatin and its long-acting analogue Sandostatin (SMS 201-995) in the management of GEP tumors. This group's experience, as well as the experience of other investigators, is presented, and the clinical utility of peptide radioimmunoassay in the field of gut endocrinology is demonstrated.