Pseudotumor of the Sigmoid Mimicking Carcinoma

On colonoscopy, the macroscopic aspect of a lesion is an important criterion for the differential diagnosis. We present a case of an apparently malignant tumor in the sigmoid. Histological investigation failed to support the diagnosis made from the gross appearance seen on colonoscopy. After surgical resection, the lesion turned out to be a reactive pseudotumor caused by fibroepithelial hyperplasia related to a severe diverticulitis with perforation of the intestinal wall.

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