Ghrelin in neuroendocrine tumors

► We examine ghrelin expression in neuroendocrine tumors (NETs). ► We review ghrelin's expression in NETs patients with carcinoids, type A chronic atrophic gastritis (CAG), with or without MEN-1, and with and without liver metastases. ► We present a review ghrelin's physiological role in NETs. ► Increasing the significance of ghrelin in NETs will provide a useful guide for future research in this field.