INS and esophageal squamous cell carcinoma: Esophageal adenocarcinoma often arises in the context of visceral obesity, which itself lowers circulating omentin-1 levels, whereas ESCC patients are typically non-obese; thus, future studies should measure omentin-1 in EAC and ESCC while controlling for visceral adiposity and insulin resistance to detect true cancer-specific changes [43].