Table 1.

Risk factors for cancer in colitis

Epithelial cell dysplasia (high-grade > low-grade)

Extent of mucosal involvement (pancolitis > distal colitis > proctitis)[3,4]

Extended duration of ongoing disease (> 8-10 yr)[1,2,5]

Severity of histologic inflammation (?linked to compliant 5-ASA use)[6,7]

Onset in childhood (?linked to underlying duration of disease)[3,4,8]

Primary sclerosing cholangitis[9,10]

Liver transplantation, usually for primary sclerosing cholangitis[11-13]

Underlying familial colon cancer risk[14,15]

Other (?immunosuppression, ?biologic agents)