Small Bowel Intussusception Secondary to Inflammatory Fibroid Polyp of the Ileum

Abstract

Introduction: Inflammatory fibroid polyps (IFP) are rare, benign, tumor-like lesions that can develop anywhere in the gastrointestinal tract. Most frequently, they are localized in the gastric antrum. Ileum is the most common site where these polyps cause small bowel obstruction. Most IFPs are polypoid masses smaller than 5 cm, although sizes up to 20 cm have been reported. Case report: We report a case of a 56-year-old man presented with progressive abdominal pain for 7 days. He denied any nausea and vomiting but did have foul smelling bloody diarrhea. His abdomen was soft, slightly distended, tympanic to percussion, and tender in left lower quadrant. Bowel sounds were hyperactive. CT scan revealed a tubular, elongated, both intraluminal and extraluminal ileal mass causing mild partial obstruction and short segment intussusception. The patient underwent resection; gross examination showed a large solid tan-white elongated mass protruding into the small bowel lumen on one side and pushing the serosal surface on the other side. The large luminal portion of the protruding tumor measured 15.0 x 5.5 x 4.0 cm, and the extraluminal portion measured 5.5 x 4.0 cm. The total length was 20.5 cm. Multiple sections showed a well demarcated, non-encapsulated, polypoid, fibrohistiocytic mass, composed of hypocellular stroma with proliferation of widely spaced bland spindled and stellate-shaped cells emdedded in a collagenous fibromyxoid stroma. The intervening stroma demonstrated prominent vascularity, diffuse eosinophils, and few scattered plasma cells with foci of benign lymphoid aggregates. No mitoses or necrosis was present. There was no other histologic evidence of malignancy. The histopathologic features, as well as the immunoperoxidase stains, were consistent with a benign, non-neoplastic tumor-like mass, consistent with a Giant Inflammatory Fibroid Polyp-Tumor Like (Vanek Tumor). Discussion: The present lesion is the largest inflammatory fibroid polyp reported to date. The ileal location is rare. Even if inflammatory fibroid polyps are benign lesions, surgical treatment is the only option when they present with intestinal intussusception. Preoperative diagnosis of inflammatory fibroid polyps is often difficult, and confirmation can only be obtained by histological and immunohistochemical examination.Figure