eP660 - Giant Colon Diverticulum: An Uncommon Presentation for a Common Disease

Purpose/Background: Giant colonic diverticulum (GCD) is an uncommon presentation in an otherwise common disease of diverticulosis. GCD is defined as a colic diverticulum larger than 4cm in diameter. With fewer than 170 case reports in literature, giant colonic diverticulum presents with a myriad of symptoms in various areas of the colon. The purpose of this case presentation is greater education and management on this topic for surgery residents and junior attending surgeons who may rarely, if ever, come across this pathology.Methods/Interventions: Patient is a 63 year old female without significant past medical history who underwent her first screening colonoscopy. On exam, there was erythematous mucosa with apparent external compression seen 45cm from the anal verge. This prompted a follow up CT scan demonstrating a large 12x12x8 cm diverticulum-like collection of stool continuous with the medial portion of the splenic flexure of the colon. This appeared to be consistent with a giant colon diverticulum. Because of the concern for impending perforation and possible harboring of malignancy, it was decided with the patient to undergo an open segmental colectomy with primary anastomosis.
She was taken to the operating room and underwent an open segmental colectomy of the splenic flexure. The diverticulum was within the colonic mesentery and communicating directly with the splenic flexure. There was no direct invasion into adjacent structures but was noted to be densely adherent. Careful mobilization was performed to separate the diverticulum from the tail of pancreas, spleen, and stomach. Once the area was resected, a side-to-side antiperistaltic anastomosis was performed. The abdomen was then closed and the patient transferred to the post-anesthesia care unit in stable condition.Results/Outcomes: Our patient did well postoperatively. She was discharged from the hospital on postoperative day three after she had full return of bowel function and tolerated a full liquid diet. The final diagnosis after pathological evaluation was a large false diverticulum with impacted fecal material, negative for dysplasia and malignancy. There were no areas of abscess or perforation identified within the specimen. The wall of the diverticulum ranged from 3mm to 5mm thick.Conclusion/

Discussion: Giant colon diverticula (GCD) are a rare but potentially emergent cause for surgical colectomy in the setting of perforation or abscess formation. The most common location for these GCD’s are within the sigmoid colon, and most commonly are the result of a contained perforation and abscess formation from diverticulosis. Surgical colectomy with primary anastomosis is the recommended management for GCD’s, given the risk of perforation, abscess formation, or potential for harboring malignancy. Colonoscopy should not be performed when these are found on imaging. The rates of malignancy within GCD’s are not well reported in literature. Further curation of data regarding the final pathology of GCD’s is warranted in order to estimate risk of concomitant malignancy, as this will further guide surgical management and follow up post-operatively."Giant Diverticulum

En bloc resection of splenic flexure and giant diverticulum.
Gross Colon Specimen

Specimen during pathology analysis.
Opened Diverticulum

Giant diverticulum after opening revealing large fecalith."