Serum IGF-1 linking visceral obesity with esophageal adenocarcinoma: unconvincing evidence.

There is a strong positive association between body mass index (BMI) and risk of esophageal adenocarcinoma. This is likely to be largely or entirely explained by the established association between central obesity and gastroesophageal reflux and between the latter and risk of esophageal adenocarcinoma. Visceral fat is also metabolically active and there is interest in the possibility that humoral factors released by this fat might promote esophageal carcinogenesis. Insulin growth factor I (IGF-1) has been studied but current data do not support circulating total IGF-1 as a humoral factor linking BMI and esophageal carcinogenesis.