GHRL and pancreatic neuroendocrine tumor: These results are also consistent with previous reports showing that native-ghrelin expression in pancreatic NETs is not clinically associated with tumor size, grade or stage [32], and with studies showing that plasma native-ghrelin concentrations lie within the normal range in patients with NETs [34, 40, 41] (native-ghrelin elevation has only been reported in three cases of ghrelinomas [41–43]).