I read with great interest the article by Collins et al1 concerning the importance of using a Roux-en-Y loop after gastric bypass. I agree completely with all of the arguments presented by the authors. However, I would like to add an important point. As the authors state, bile reflux is an important pathogenic factor in the development of adenocarcinoma in rat esophagi and can be prevented by Roux-en-Y anastomosis. We have been performing a unique experimental procedure in patients with long-segment Barrett syndrome: partial gastrectomy and Roux-en-Y gastrojejunostomy.2,3 We have shown that with a follow-up of more than 10 years postoperatively, intestinal metaplasia can regress to cardiac mucosa in more than half of patients; but what is more important is that none of the patients have progressed to high-grade dysplasia or adenocarcinoma.4 Even low-grade dysplasia can regress to nondysplastic mucosa.5 This operation has proven to be a true antineoplastic procedure compared with classic antireflux surgery, after which adenocarcinoma can develop. We have also demonstrated that among patients with morbid obesity and Barrett syndrome, intestinal metaplasia can disappear after gastric bypass.6 I believe the authors should include this unique human clinical-experimental data in addition to the studies in rats.