Successful Endoscopic Submucosal Dissection for Giant Inflammatory Fibroid Polyp in Terminal Ileum

A 55-year-old woman presented with postprandial abdominal pain and diarrhea. Contrast-enhanced abdominal computed tomography revealed a large tumor in the ileocecal region. Colonoscopy demonstrated a pedunculated polyp originating from the terminal ileum, intermittently prolapsing into the cecum with a stalk-like base. Biopsy specimens showed nonspecific inflammatory changes. Initial hot snare polypectomy was unsuccessful due to the polyp's large size and mobility. Therefore, endoscopic submucosal dissection using the underwater pocket-creation method was performed, with the polyp stabilized using a traction device anchored to its apex and the opposite side of the ileocecal valve. This technique enabled safe resection of the lesion from its broad stalk. Although marked submucosal fibrosis was observed beneath the lesion, en bloc resection was successfully completed without perforation in 63 min. Retrieval of the resected specimen via conventional endoscopic methods was unsuccessful due to difficulty passing through the hepatic flexure. Instead, the specimen was retrieved following natural elimination the next day. The resected specimen was a prolate spheroid measuring 62 × 40 × 22 mm. Histopathological examination confirmed an inflammatory fibroid polyp (IFP), consisting of edematous stroma with dense inflammatory cell infiltration. The patient resumed oral intake on postoperative day 2 and had an uneventful recovery. Follow-up colonoscopy at 6 months revealed no residual or recurrent lesion. To our knowledge, this case represents the largest IFP of the small intestine ever resected endoscopically. For a giant, mobile lesion in the terminal ileum, the combination of the pocket-creation method, underwater technique, and lesion anchoring was an effective strategy.