A case of ileal adenoma successfully treated by endoscopic submucosal dissection

A 74-year-old woman undergoing follow-up colonoscopy for constipation was incidentally found to have a 10-mm reddish, flat elevated lesion located 10 cm proximal to the ileocecal valve. Magnified narrow-band imaging showed relatively regular vessel and surface patterns, consistent with a JNET Type 2A-like lesion. Biopsy revealed a low-grade intestinal-type adenoma. Considering the need for complete resection, endoscopic submucosal dissection (ESD) was performed. Although technically demanding in the small intestine, stable visualization and maneuverability were achieved. Gel immersion ESD facilitated mucosal incision and careful submucosal dissection. Histopathology demonstrated a high-grade intestinal-type adenoma confined to the mucosa with negative margins. This case suggests ESD is feasible for selected ileal adenomas.