Is colonoscopic cancer surveillance in ulcerative colitis essential for every patient?

Surveillance aims to diagnose precancer or cancer at a surgically curable stage. Cancer complicating ulcerative colitis affects only 1-2 per million of the general population annually. The risk is low within 10 years of disease onset, and in proctitis or left-sided colitis. It is approximately one in 120 per year for those with extensive disease after 10 years from onset. Results of surveillance programmes from regional hospitals among 423 patients led to surgery for precancer or cancer once every 123 colonoscopies; there were no cancer deaths during surveillance and all 4 cancers were Dukes' stage A or B. At referral centres, many patients have dysplasia at the first colonoscopy. Two-thirds of cancers in colitis develop in the recto-sigmoid; flexible sigmoidoscopy has a role in surveillance which is untested. Colonoscopic surveillance is not appropriate for most patients with colitis; it is worthwhile but not essential for those with long-standing extensive disease.