AIM:To investigate the effects of Helicobacter pylori (H pylori ) eradication therapy for treatment of peptic ulcer on the incidence of gastric cancer.

A 45-year-old Japanese man who had been suffering from intestinal-type Behcet's disease was referred to Yamagata University Hospital for enteroscopic examination. Double balloon enteroscopy was performed via the anal route. We identified ulceration of the terminal ileum that was detected previously. In addition, we incidentally recognized a Meckel's diverticulum coexisting with a heterotopic mucosal island nearly 100 cm on the oral side from the ileocecal valve. Meckel's diverticulum did not accompany ulcers and there was no history of bleeding. The heterotopic mucosal island was confirmed as gastric mucosa from biopsy specimens. High-resolution endoscopic features of heterotopic gastric mucosa in Meckel's diverticulum using a double balloon enteroscopy are considered informative images.