Successful endoscopic submucosal dissection of a giant polyp in a 21-month-old female

Figure 1 Imaging. A: An abdominal computed tomography scan shows a large, nodular soft tissue mass occupying the pylorus and extending into the duodenum; B: Ultrasonography shows marked thickening of the mucosal and muscular layered lesion at the pylorus and duodenum.

Figure 2 Endoscopic views. A: Endoscopy shows a diffuse hyperemic and edematous giant lobulating mass from the pylorus to the duodenal inlet. B: The mass lifted easily and was resected in one piece endoscopically.

Figure 3 Retrieved pieces of the large polyp were reconstructed.

Figure 4 Photomicrograph of the polyp with thick-walled vessels and organized thick bundles of arborizing smooth muscle with a prominent basal glandular component.