Environmental pollutants in gallbladder carcinogenesis

Gallbladder cancer is a common malignancy of the gastrointestinal tract that shows wide geographical variation in its distribution. Cause of gallbladder cancer is still obscure; however, various etiological factors have been proposed. Of these gallstones and inflammation of the gallbladder is commonest. Despite three decades of active research no conclusive evidence is available as to what causes gallbladder cancer? In this article we reviewed the evidence on the role of environmental pollutants on gallbladder carcinogenesis. A detailed search of Medline was carried out which revealed only 12 articles. A number of heavy metals like nickel, cadmium, etc. have been implicated; however, the evidence is not robust enough to conclude its association. Role of radiation and pesticides in river water have also been evaluated without any conclusive evidence of its association with gallbladder cancer. Better designed case-control studies or cohort studies looking at exposure are required before it could be accepted as one of the causes of GBC.