Risk of thiamine deficiency and Wernicke's encephalopathy after gastrointestinal surgery for cancer.

Background: Cancer patients submitted to gastrointestinal surgery are at risk of thiamine deficiency (TD) and Wernicke's encephalopathy (WE). Although permanent neurological damage and death could be prevented by a timely replacement therapy, they often remain undiagnosed and untreated. We hypothesized that WE remains unrecognized because most cases may manifest several months after hospital discharge.