GSTM2 and Barrett adenocarcinoma: The genetic variations can change an individual's susceptibility to carcinogens and toxins as well as affect the toxicity and efficacy of certain drugs.[30,31] Diseases associated with GSTM2 include Barrett's Adenocarcinoma[32] and Hepatocellular Carcinoma.[33] Therefore, the low GSTM2 expression in ACC might be the cause of ACC pathogenesis and progression.