Table 1. Characteristics of Included Articles.
| Source | Country | Article type | Study period | Source of cohort data | IBD population size, No. | Reference population size, No. | Cancer events in IBD population, No. | Cancer events in reference population, No. | RR estimate for cancer in pediatric-onset IBD (95% CI) | Follow-up time of IBD population, PY per year | Adjusted confounders | % of Female patients | Cancer incidence in IBD population | Median (IQR) age, y | NOS Scorea | |||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| CD | UC | CD | UC | At IBD diagnosis | At cancer diagnosis | |||||||||||||
| El-Matary et al,12 2020 | Canada | BC | 1984 to 2018 | University of Manitoba IBD Epidemiology Database13 (South-central Canada: Manitoba Province) | 576 | 371 | 9272 | NR | NR | 75 | HR, 2.00 (1.16-3.44) | 14 938 | Sex, age, region, or residence | NR | Incidence rate, 1.1 (per 1000 PY) | 14 (12-16) | 37 (24-45) | 4 (Fair) |
| Kjaergaard et al,14 2020 | Denmark | BC | 1977 to 2018 | Danish national patient registry | 2673 | 2707 | 53 800 | 77 | 81 | 701 | HR, 2.16 (1.81-2.57) | 77 821 | Sex, age, calendar, and year of diagnosis | NR | Incidence rate, 2.03 (per 1000 PY) | NR | NR | 8 (Good) |
| Malham et al,15 2019 | Finland | ORA | 1992 to 2014 | Finnish national patient registries | 1261 | 2084 | 2 899 565 | 10 | 24 | 8160 | SIR, 3.60 (2.55-5.09) | 33 845; median, 9.0 (IQR, 4.4-15.0) | NR | 44.4 | Incidence rate, 1.0 (per 1000 PY) | 14 (12-16) | 23.5 (14-34) | 5 (Fair) |
| U-IBD = 11b | ||||||||||||||||||
| Olén et al,16 2017 | Sweden | ORA | 1964 to 2014 | Swedish Patient Register | 3768 | 4648 | 92 870 | 153 | 299 | 2256 | HR, 2.20 (1.97-2.46) | 148 682 | Sex, age, year of birth, and region of residence | 44.7 | Incidence rate, 3.3 (per 1000 PY) | 15 (12-16) | Not reported | 9 (Good) |
| U-IBD = 989c | U-IBD = 45c | |||||||||||||||||
| Peneau et al,17 2013 | France | ORA | 1988 to 2004 | EPIMAD registry18 (Northern France: Seine-Maritime, Somme, Pas-de-Calais and Nord Departements) | 538 | 160 | 775 | 6 | 3 | 3 | SIR, 3.00 (1.40-6.40) | 8254; median, 11.4 (IQR, 7.4-15.8) | Sex and age | 48.4 | Crude cancer rate, 1.3% | 14.6 (11.5-16.1)d | 29.6 (21.5-33.1) | 5 (Fair) |
| U-IBD = 26c | ||||||||||||||||||
Abbreviations: BC, brief communication; CD, Crohn disease; EPIMAD, Epidémiologie des maladies inflammatoires de l’Intestin; HR, hazard ratio; IBD, inflammatory bowel disease; NOS, Newcastle-Ottawa Scale; NR, not reported; ORA, original research article; PY, person-years; RR, relative rate; SIR, standardized incidence ratio; UC, ulcerative colitis; U-IBD, unclassified IBD.
a
Agency for Healthcare Research and Quality standard.
b
Number of cases excluded from overall IBD meta-analysis.
c
Number of cases included in overall IBD meta-analysis.
d
Pediatric-onset defined as 17 years or younger at diagnosis.