Ulcerative colitis-associated colorectal cancer

Table 2 Timing of surveillance colonoscopy for colorectal cancer in ulcerative colitis

Ref.	Year	Guidelines	Beginning of surveillance (years after onset of symptoms)	Surveillance schedule
Van Assche et al[73]	2013	European Crohn’s and Colitis Organization (ECCO)	8 yr	High risk1; 1-2 yr
				Low risk1; 3-4 yr
Farraye et al[72]	2010	American Gastroenterological Association (AGA)	8 yr	Extensive colitis or left-sided colitis; 1-2 yr
				Patients with PSC; 1 yr
				High-grade or low-grade dysplasia; colectomy or repeat colonoscopy within 6 mo
				Indefinite dysplasia; 3 to 12 mo
				No dysplasia; 1-2 yr
Kornbluth et al[70]	2010	American College of Gastroenterology (ACG)	8-10 yr	1-2 yr
Cairns et al[68]	2010	British Society of Gastroenterology (BSG)	10 yr	lower risk2; 5 yr
				intermediate risk3; 3 yr
				higher risk4; 1 yr
Leighton et al[69]	2006	American Society for Gastrointestinal Endoscopy (ASGE)	8-10 yr	1-2 yr(indefinite dysplasia: 3 to 6 mo)
Eaden et al[71]	2002	United Kingdom	8-10 years (pancolitis)	3 yr (second decade)
			15-20 yr (left-sided colitis)	2 yr (third decade)
				1 yr (fourth decade)

¹Low-risk is 0-2 points and high-risk is 3-4 points; Risk factor: Pancolitis, endoscopic and/or histological inflammation, pseudopolyps, and family history of CRC: each risk factor is counted with one point;

²lower risk: extensive colitis with no active inflammation or left-sided colitis;

³intermediate risk: extensive colitis with mild active inflammation or post-inflammatory polyps or family history CRC in FDR aged ≥ 50;

⁴higher risk: active inflammation or stricture in past 5 years or dysplasia in past 5 years declining surgery or PSC/transplant for PSC or family history CRC in FDR aged < 50. PSC: Primary sclerosing cholangitis; CRC: Colorectal cancer; FDR: First-degree relatives.