Polyposis in ulcerative colitis.

One hundred and fifty cases of ulcerative colitis were assessed by total colonoscopy with multiple biopsies. Inflammatory polyposis was found in 25 (17%) cases and six of these had a large (greater than 1-5 cm) solitary polyp which radiologically resembled carcinoma in four cases. Adenomatous polyps were discovered in four cases. Three carcinomas were found at endoscopy, of which two were entirely unsuspected. In all cases endoscopic polypectomy or surgical intervention was performed to establish the exact histological diagnosis.