Cancer surveillance in ulcerative colitis

There is an increased risk of developing colorectal carcinoma in patients with longstanding UC (1). The risk of development of cancer is dependent on the duration and the extent of the disease.

The risk of developing colorectal carcinoma is highest in patients with extensive colitis, intermediate in patients with left-sided colitis and not increased in proctitis (1)

The risk of colorectal cancer (CRC) in people with ulcerative colitis is increased in:

• patients with early onset disease (age below 20 years at onset of disease) (2)
• patients with UC-associated primary sclerosing cholangitis
• persistent inflammation
• family history of CRC

If the patient has a pancolitis then:

• after 10 years risk is 1
• after 20 years risk is 13%
• after 30 years risk is 34%

It is conjectured that neoplasms are preceded by initially mild and later severe dysplasia of the colonic epithelium. Surveillance in the form of colonoscopy with multiple biopsies every 18-24 months is designed to identify such premalignant changes.

Advice people that:

• the risk of colorectal carcinoma appears to increase 8-10 years after the onset of Ulcerative colitis related symptoms
• screening colonoscopy should be done 8-10 years after the onset of UC symptoms (1)

In the surveillance schedule

• after the initial colonoscopy screening for extensive colitis, surveillance should be carried out every other year up to year 20 of disease, then annually.
• in left-sided or distal UC, surveillance should start 15 years after the onset of disease
• proctitis does not require further surveillance (1)

Note - in the UK, colonoscopic surveillance is recommended for all patients, starting about ten years after the onset of symptoms, except for those with ulcerative proctitis that is documented on two consecutive endoscopic examinations, who do not require surveillance (3)

Reference:

1. Travis SPL et al. European evidence-based Consensus on the diagnosis and management of ulcerative colitis: Current management. Journal of Crohn's and Colitis (2008) 2, 24-62
2. Olen O, Askling J, Sachs MC, et al; Childhood onset inflammatory bowel disease and risk of cancer: a Swedish nationwide cohort study 1964-2014. BMJ. 2017 Sep 20;358
3. Colonoscopic surveillance for prevention of colorectal cancer in people with ulcerative colitis, Crohn's disease or adenomas; NICE Clinical Guideline (March 2011 - last updated September 2022)