GHRL and cancer: Two of three studies investigating serum ghrelin levels in colon or colorectal cancer found significantly decreased levels in the cancer patients vs controls (D’Onghia et al. 2007, Kemik et al. 2010), including one, in 29 patients with colorectal cancer and 50 controls, that also found ghrelin serum levels were significantly inversely associated with tumor stage (D’Onghia et al. 2007) (Table 1).