Rare Case of a Colocolonic Intussusception Due to Giant Lipoma

Abstract

Adult bowel intussusceptions are rare and represent 1% of all bowel obstructions in this population. Malignancies are the most common cause of lead point for colo-colonic intussusceptions. We present a rare case of a colo-colonic intussusception due to a benign, 7 cm lipoma. 56 y/o male with unremarkable past medical history presents to the emergency department complaining of a one month history of progressive left lower quadrant crampy abdominal pain with sudden development of constipation, two events of hematochezia and no systemic symptoms. No family history of GI malignancies and no previous screening colonoscopy. His initial laboratory work up was unremarkable including hemoglobin of 13.6 g/dl. A CT abdomen/pelvis with IV and oral contrast was performed and showed a 7.1 by 3.8 cm teardrop shaped fat density mass located in the descending/sigmoid colon with evidence of intussusception (image 1). A colonoscopy was performed showing a larger pedunculated mass with a thick stalk and an ulcerated surface (image 2 and 3). Due to his clinical presentation and size of the mass the patient underwent a left colectomy. Pathology evaluation of the mass showed a tumor involving the submucosa with evidence of mature adipocytes consistent with a giant lipoma. Bowel intussusceptions account for 1% of all adult bowel obstructions. Colo-colonic intussusceptions, due to giant lipomas (lesions over 4 cm), are rare with around 50 cases reported in the last decade. The diagnosis is usually made with a radiologic study, with CT scan being the recommended modality. Asymptomatic large lipomas can be successfully removed by endoloop in a grab and let go technique. For symptomatic lesions, including intussusception, the therapy of choice is surgery. However, in the last few years several case reports have shown the possibility of endoscopic resection (unroofing/electrocautery) using endoscopic ultrasound and lifting techniques with good success and low complication rates. We present a rare case of a colo-colonic intussusception with a giant lipoma. As in our case, these lesions tend to lose the classic well-delineated sub mucosal bulging, making it hard to differentiate between a benign lipoma and malignancy. As we continue to improve our endoscopic technics and equipment, endoscopic resections could be feasible even in the symptomatic lesions. If endoscopic resection is contemplated, surgical support should be available in case of a perforation or major bleeding.Figure 1Figure 2Figure 3