Presentation
Left lower abdominal pain in a patient with a history of left mastectomy for breast cancer on follow-up.
Patient Data
Colosigmoid intussusception (length over 7 cm) with a target sign. A well-defined submucosal fat-containing sigmoid mass (mean density = - 80 HU) acting as a lead point measuring 54 x 36 x 26 mm. No dilatation of the descending colon proximal to the intussusception. Moderate thickening of the sigmoid colon distal to the fat-containing mass (probably reactive). No free fluid or gas in the peritoneal cavity.
No abdominal metastatic lesion is seen.
Case Discussion
CT features of colo-colonic intussusception secondary to a sigmoid lipoma, well-demonstrated at the lead point of the intussusception. At surgery, it was a submucosal lipoma with no malignancy of the sigmoid colon.
Adult large bowel intussusception is rare and most cases are of malignant origin 1,2. Large bowel lipoma is very rare but considered the most common benign cause of colo-colonic intussusception in adults 1,2.