Table 1 Patient stratification: eligibility criteria

Pre-colectomy (Fig. 2a)

• Patients with an intact colon/rectum considering prophylactic surgery

Retained rectum/ileal pouch polyposis (Fig. 2b)

• Patients with ≥3 years since colectomy with IRA/proctocolectomy with pouch and demonstrating polyposis as defined by Stage 1, 2, 3^a:

 − Stage 1: 10–25 polyps, all <5 mm

 − Stage 2: 10–25 polyps, at least one >1 cm

 − Stage 3: >25 polyps amenable to complete removal, or any incompletely removed sessile polyp, or any previous evidence of high-grade dysplasia, even if completely removed

• For all patients, any rectal/pouch polyps >5 mm must be excised at baseline

Duodenal polyposis (Fig. 2c)

• Patients with ≥1 of the following:

 − Current Spigelman Stage 3 or 4

 − Patients who had previous surgical endoscopic intervention ≤6 months for Spigelman Stage 3/4 that may have been down-staged to Spigelman 1/2