A Vanishing Polyp: A Large Ileal Lipoma Causing Ileocolic Intussusception.

Intussusception is defined as invagination of a proximal segment of gastrointestinal tract into distal segment and is an uncommon pathology. It is more common in children. In the adult population, it is often due to a polyp or tumor. We report an interesting case of a vanishing colonic polyp in a 55-year-old man who presented with a three-month history of intermittent right abdominal pain, altered bowel habit, and weight loss. Colonoscopy demonstrated a large, elongated polyp in the ascending colon, which vanished during attempts to intubate proximally. A computed tomography scan showed a lipomatous polyp in the distal ileum confirmed on a repeat colonoscopy. The patient proceeded with surgical resection, and histology confirmed the polyp to be an ileal submucosal lipoma. There is literature on ileocolic intussusceptions secondary to ileal submucosal lipoma; however, our case is interesting and unique in that the intussusception was seen and reduced during the colonoscopy.