Polypoid lesions rarely occur in the ileal pouch in ulcerative colitis patients after restorative proctocolectomy. Clinical features, malignant potential, and management of pouch polyps have not been characterized. We identified 23 ulcerative colitis patients with large polyps (size> or =1 cm) of the ileal pouch from our 2,512-case ulcerative colitis pouch database. Demographic, clinical, endoscopic, and histologic data were reviewed. The Pouchitis Disease Activity Index symptom score (range, 0-6) was used to quantify patients' symptoms before and after polypectomy. Of the 23 patients, 95.7 percent (22 patients) had pouch endoscopy indicated for the evaluation of symptoms when polyps were detected, and 60.9 percent of patients had the polyps in the pouch, 26.1 percent in the anal transitional zone, and 21.7 percent in the afferent limb. The mean size of pouch polyps was 1.9 cm +/- 1 cm. Twenty-one patients (91.3 percent) had concomitant pouchitis, cuffitis, or Crohn's disease. On histology, 21 patients (91.3 percent) had inflammatory-type polyps, and 2 (8.7 percent) had dysplastic or malignant polyps. In 18 patients who had endoscopic polypectomy with concurrent medical therapy, the prepolypectomy and postpolypectomy mean symptom scores were 3.4 +/- 1.7 and 1.1 +/- 1.2 points, respectively (P = 0.015). Two patients (8.7 percent) had pouch excision for malignancy or for concomitant chronic refractory pouchitis. The majority of patients with large ileal pouch polyps were symptomatic. These polyps were typically detected on the background of pouchitis, cuffitis, or Crohn's disease. Although the majority of polyps were inflammatory type, polyps in two patients were dysplastic or malignant. Endoscopic polypectomy with concomitant medical therapy seemed to improve patients' symptom scores.