GHRL and colorectal cancer: In the largest, gastrointestinal cancer group (including gastric, esophageal and colorectal cancers), several population-based, long-term, prospective studies showed an inverse association of baseline ghrelin level with risk of gastric, esophagogastric and esophageal cancer incidence (de Martel et al. 2007, Murphy et al. 2011, Murphy et al. 2012).