V99 - When the Cecum Meets the Rectum: Ileorectal Intussusception Secondary to Cecal Adenocarcinoma

CME Eligible

Purpose/Background: Adult bowel intussusception is rare, accounting for less than 5% of all cases and about 1% of bowel obstructions. Unlike pediatric cases, adult intussusception is usually secondary to a pathologic lead point such as a benign or malignant mass. Because symptoms are often intermittent and nonspecific, diagnosis can be challenging. We present a rare case of ileorectal intussusception secondary to a cecal adenocarcinoma, highlighting the diagnostic complexity and surgical management of this unusual presentation.

Methods/Interventions: A 67-year-old female with no significant medical history presented to the emergency department with 10 days of emesis and abdominal pain. She had been undergoing workup at an outside facility for anorexia and diarrhea. Colonoscopy demonstrated a mass at 55 cm, but the endoscopist was unable to traverse it. Biopsies revealed fragmented tubulovillous adenoma, and CT colonography was performed to complete the evaluation, demonstrating a 5-cm cecal mass. The patient had been offered a minimally invasive left colectomy but, due to uncertainty regarding the mass's location, sought a second opinion and presented to the ED before outpatient evaluation.

On arrival, her abdomen was soft with fullness in the left lower quadrant. Digital rectal exam confirmed a palpable firm mass. CT abdomen and pelvis with IV contrast demonstrated a long-segment ileocolic intussusception with the cecal mass extending into the mid-rectum. Flexible sigmoidoscopy was performed in an attempt to reduce the intussusception, but reduction was unsuccessful. The patient subsequently underwent exploratory laparoscopy with attempted reduction, which was also unsuccessful. The procedure was converted to exploratory laparotomy, during which the cecum was first manually reduced from the rectum to the ascending colon. A right colectomy with diverting loop ileostomy was performed. The patient tolerated the procedure well and was managed under an ERAS protocol.

Results/Outcomes: The patient regained bowel function by postoperative day two and was discharged on day three. Final pathology revealed invasive colonic adenocarcinoma arising in a tubulovillous adenoma with high-grade dysplasia with 32 benign lymph nodes. She was referred to medical oncology for adjuvant therapy evaluation.

Conclusion/Discussion: While most adult intussusceptions have an underlying neoplastic lead point, involvement of the entire ileocolic segment extending into the rectum is exceedingly uncommon, with fewer than five reported cases in the literature. This video presentation highlights the diagnostic challenges associated with this condition and demonstrates the successful application of surgical management of ileorectal intussusception. Awareness of this rare presentation can facilitate earlier recognition and timely surgical management, ultimately improving patient outcomes.

CT Abdomen/Pelvis with IV contrast - coronal view