LAUSR

A 74-year-old man underwent a CT examination for intermittent lower abdominal pain. The images revealed a tumor in the ileocecal region (Fig. 1A). Endoscopic examination showed the lesion to be a soft, yellowish submucosal tumor measuring 40 mm in diameter located in the terminal ileum (Fig. 1B). The lesion fully occupied the lumen; it moved to the cecum when pulled but immediately returned to the ileum upon insufflation (Fig. 1C). Based on CT and endoscopic findings, we made a diagnosis of lipoma. Because the huge tumor was thought to be the cause of the patient’s intermittent abdominal pain, we decided to remove the tumor by endoscopic submucosal dissection (ESD). The entire procedure is shown in the video (Video 1, available online at www.VideoGIE.org). A DualKnife (Olympus, Tokyo, Japan) was used as the endo-device, and local injection of hyaluronic acid was administered. The tumor had to be extracted into the cecumwith forceps because it had become stuck in the ileum because of the insufflation. First, upon making the incision and dissecting along the ileal side as upstream as possible to the ileocecal valve, we found that the tumor had completely migrated into the cecum without being stuck to the ileum (Fig. 2A and B). Because the dissection revealed that the tumor had invaded the muscular layer, it was necessary to partially dissect the muscular layer. The incision was then made circumferential by making an additional incision on the cecal side, and the remaining submucosal layer was dissected, which made it