Management of gastro-entero-pancreatic neuroendocrine tumours (GEP NET) : an introduction

Since the discovery of secretin by Bayliss and Starling in 1902 many hormones have been identified in the gut, so that the gastro-intestinal-pancreatic tract can be con- sidered the largest endocrine organ in the human body. Gut endocrine cells constitute a complex regulatory net- work for local control of secretion, absorption, motility, mucosal cell proliferation and differentiation. Endocrine committed cells in the gut may undergo proliferative changes leading to hyperplastic and dys- plastic lesions and sometimes giving origin eventually to gut or pancreas endocrine tumours, also called neuroen- docrine tumours (NET) (1). They are characterized his- tologically by the intracellular presence of markers of endocrine tissue, such as chromogranin A and neuron- specific enolase, which can be used in the diagnosis of these tumours.