| Obstructing sigmoid polyp | |
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| The polyp is filling up nearly the whole intestinal lumen. Itīs size is 6 x 6 cm, the diameter at the base is 3 cm. An endoscopic removal is not feasible. Histology of the surgically excised polyp reveals a tubulovillous adenoma harbouring a carcinoma in situ (Tis). | |
