Plasma N-acetyl-glucosaminidase in advanced gastro-intestinal adenocarcinoma correlates with age, stage and outcome.

N-acetyl-glucosaminidase (NAG) is a potential marker of genotoxicity. We retrospectively analyzed plasma NAG and clinico-pathologic features in advanced gastrointestinal adenocarcinoma patients. Plasma from 118 patients and 51 healthy volunteers was analyzed for associations between NAG levels and age, disease presence, stage, treatment responses and survival. Pretreatment NAG correlated with age but was independently increased in metastatic versus locally advanced disease, particularly in gastric/esophageal patients. NAG was also associated with reduced overall survival. In subgroup analysis, increased NAG activity between day 1 and 2 of chemotherapy cycle 1 correlated with treatment response. We demonstrated that NAG correlates with gastrointestinal cancer outcomes. Further studies are required to determine if plasma markers of genotoxicity can be useful for disease monitoring.