Incarcerated Rectal Prolapse Secondary to Rectal Adenomatous Polyposis: A Case Report

Incarcerated or strangulated prolapsed rectal polyps are an incredibly rare phenomenon, seldom reported in the literature. Given the overall low incidence of rectal prolapse, these instances in which polyposis - a relatively common condition - progress and become emergent are clinically significant. We present a case of a 49-year-old with an acutely incarcerated rectal prolapse of dysplastic villous adenomatous polypoid tissue. The patient presented to our facility with a large, painful rectal mass, passing mucus and bright red blood per rectum after two hours of straining to have a bowel movement. She denied past colonoscopies, anal receptive intercourse, and any personal or family history of bowel disease or cancer. On computed tomography (CT) scans, the incarcerated mass appeared as a full-thickness rectal prolapse with signs of edema and ischemia, prompting emergent surgical intervention. A diagnostic laparoscopy showed no pathology to the large bowel or rectum. The prolapsed mucosal mass was circumferentially resected, and the rectum was reduced. A temporary diverting loop sigmoid colostomy was then created. Surgical pathology reported villous adenoma, extensive high-grade dysplasia, and foci of pseudo-invasion with no evidence of invasive carcinoma. A follow-up rectal exam under anesthesia and flexible sigmoidoscopy identified multiple large rectal polyps but no evidence of rectal ischemia. The patient had an uneventful postoperative course and was discharged home on hospital day 11 for outpatient follow-up with Colorectal Surgery. Abdominal perineal resection versus transanal transabdominal rectal resection, preserving gastrointestinal continuity, have been offered as options for definitive treatment. Rectal prolapse can be predisposed to occur in the setting of a variety of clinical conditions. Management of prolapses can be complex. In the setting of these rare incarcerated or strangulated prolapsed dysplastic polyps, emergent surgical intervention is still indicated.