Clin Endosc.  2023 Jan;56(1):119-124. 10.5946/ce.2021.081.

A large and pedunculated inflammatory pseudotumor with pseudosarcomatous change of the cecum mimicking a malignant polyp: a case report and literature review

• Oh JS
• Kim HW
• Park SB
• Kang DH
• Choi CW
• Kim SJ
• Nam HS
• Ryu DG

• KMID: 2538760
• DOI: http://doi.org/10.5946/ce.2021.081

Abstract

Inflammatory pseudotumor (IPT) is a rare benign tumor of unknown etiology that can occur in almost any organ system. It has neoplastic features such as local recurrence, invasive growth, and vascular invasion, leading to the possibility of malignant sarcomatous changes. The clinical presentations of colonic IPT may include abdominal pain, anemia, a palpable mass, and intestinal obstruction. A few cases of colonic IPT have been reported, but colonic IPT with pedunculated morphology is very rare. Furthermore, since it can mimic malignant polyps, understanding the endoscopic findings of colonic IPT is important for proper treatment. Herein, we present a case of colonic IPT with pseudosarcomatous changes, presenting as a large polyp, mimicking a malignant polyp in the cecum, along with a literature review.

Keyword

Cecum; Inflammatory pseudotumor; Pedunculated polyp

Figure

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  Fig. 1. Abdominal computed tomography images. (A) A well-enhancing soft-tissue mass (blue arrow), measuring approximately 4 cm, at the ascending colon. (B) Increased colonic wall thickness (red arrow) of the ascending colon and cecum.

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  Fig. 2. Colonoscopic findings. (A, B) An approximately 4–5 cm polypoid mass with a short stalk, thickly coated exudates, mucosal desquamation, and deep ulcers originating in the cecum.

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  Fig. 3. Gross and pathologic findings. (A) A well-defined pedunculated mass at the cecum. (B) Ulceration (red arrow) with marked pleomorphic cell proliferation limited to the mucosa and submucosa (hematoxylin and eosin stain, ×6). (C) Marked pleomorphic cell (red arrows) and spindle cell proliferation (yellow arrows) with severe neutrophil infiltration (blue dotted arrows) (hematoxylin and eosin stain, ×200).

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