GCG and gastric cancer: Higher levels of Nts/NPs were noted in pCRC versus control (serotonin, ET-1, big ET-1, galanin, G17, GLP1/GLP2, NT, PYY and SP), as well as in metastatic CRC than pCRC (gastrin, VIP), metastatic CRC versus control (ET-1) or in CRC compared to other types of GIT cancer (pancreatic, gastric cancers) (NT, VIP).