Inflammatory bowel disease-related colorectal cancer: Past, present and future perspectives

Table 1 The difference in the incidence of inflammatory bowel disease related colorectal cancer, past and present

Epidemiology		CRC in ulcerative colitis	CRC in indeterminate colitis	CRC in Crohn's disease
Annual incidence	Past	Stewénius et al[111], 1995, 1.4/1000 PYD; Eaden et al[2], 2001, 2/1000 PYD-after 10 yr of initial onset; 7/1000 PY (patients with extensive colitis 90%) 30 yr of initial onset; Castaño-Milla et al[112], 2012, 1.01/1000 PYD - after 10 yr of initial onset; 3.75/1000 PYD - after 20 yr of initial onset; 5.85/1000 PYD - after 30 yr of initial onset	Stewénius et al[111], 1995, 2.4/1000 PYD	Olén et al[113], 2020, a Scandinavian population-based cohort study 0.31 per 1000 PY(1968); Laukoetter et al[114], 2011, 0.5/1000 PYD
	Present	Fumery et al[115], 2017, the annual incidence of CRC was 0.8% (95%CI: 0.4-1.3)		Olén et al[113], 2020, a Scandinavian population-based cohort study 0.47 per 1000 person-years (2017)
Risk	Past	Eaden et al[2], 2001, 0.3% after 30 yr of initial onset		Canavan et al[3], 2006, 2.9% after 10 yr of initial onset; 5.6% after 20 yr; 8.3% after 30 yr. Friedman et al[116], 2008, 7% by 10th surveillance (patients with extensive colitis 90%). Basseri et al[117], 2012, 5.6% by 10th surveillance (patients with extensive colitis 55%)
	Present	Fumery et al[115], 2017, the risk of CRC was higher when LGD was diagnosed by an expert gastrointestinal pathologist (1.5%) than by community pathologists (0.2%). Factors significantly associated with dysplasia progression were concomitant: PSC (OR, 3.4; 95% CI: 1.5-7.8); Invisible dysplasia (vs visible dysplasia; OR, 1.9; 95% CI: 1.0-3.4), distal location (vs proximal location; OR, 2.0; 95% CI: 1.1-3.7); Multifocal dysplasia (vs unifocal dysplasia; OR, 3.5; 95% CI: 1.5-8.5)	Keller et al[118], 2019, IBD-CRC is responsible for approximately 2% of the annual mortality from CRC overall, but 10%-15% of the annual deaths in IBD patients	Olén et al[113], a Scandinavian population-based cohort study. Patients with Crohn's disease who were diagnosed with CRC were at increased risk of CRC mortality compared with reference individuals also diagnosed with CRC [HR 1.42 (1.16-1.75) when adjusted for tumour stage]

PYD: Patient year days; LGD: Low-grade dysplasia; CRC: Colorectal cancer; IBD-CRC: Inflammatory bowel disease-related colorectal cancer; PSC: Primary sclerosing cholangitis; HR: Hazard ratio; OR: Odds ratio; CI: Confidence interval.