Table 1.
Childhood onset inflammatory bowel disease and risk of cancer
| Study | Study period | Age at onset, years | No of patients followed (subtype) | Patient years of follow-up | Number of cancers diagnosed | Incidence per 1000 person years (95% CI) | Relative risk* |
|---|---|---|---|---|---|---|---|
| Devroede, 1971 | USA 1919-65 | <14 | 396 (UC) | NR, max 43 years | 52 (any cancer) | NR | NA |
| Weedon,1973 | USA 1919-65 | <22 (mean 15) | 449 (CD) | 7077 | 12 (any cancer) 8 (CRC) |
1.0 (0.5 to 2.1) for CRC | 20 for CRC |
| Goel, 1973 | Scotland 1931-71 | <14 (mean 8) | 25 (UC) | 303 | 1 (CRC) | 3.3 (0.2 to 16.3) | NR |
| Ekbom, 1990 | Sweden 1945-83 | <15 | 363 (UC) | 4220 | 13 (CRC) | 3.1 (1.7 to 16.3) | 118 (63 to 202) |
| Ekbom, 1990 | Sweden 1983-84 | <30 | 964 (CD) | 12 025 | 5 (CRC) | 0.4 (0.2 to 0.9) | 10 (3 to 23) |
| Ashworth, 2012 | USA 1979-2009 | <22 (mean 12) | 839 (UC,CD) | 4441 | 2 (lymphoma) | 0.5 (0.1 to 1.5) | 8 (0.7 to 42) |
| Jess, 2012 | Denmark 1979-2008 | <20 | 4763 (UC,CD) | 52 100 | 18 (CRC) | 0.3 (0.2 to 0.5) | UC: 44 (27 to 719) CD: 2 (0.3 to 17) |
| Peneau, 2013 | France 1988-2009 | <17 (median 14) | 698 (UC,CD) | NR, median 12 years | 9 (any cancer) | NR | 3.0 (1.3 to 5.9) |
| de Ridder, 2014 | Europe 2006-11 | <19 (median 12) | NA | NA | 18 (any cancer) | NA | NA |
| Kappelman, 2014 | Denmark 1978-2010 | <20 | NR (UC,CD) | NR | NR | NR | UC: 2.0 (1.4 to 2.7) CD: 2.3 (1.5 to 3.4) |
| Hyams, 2017 | USA, Europe 2007-16 | <17 | 5766 (UC,CD) | 24 543 | 15 (any cancer) 9 (lymphoid) |
0.6 (0.4 to 1.0)† | Thio exposed: 2.9 (1.4 to 5.1) Non-exposed: 1.3 (0.2 to 4.7) |
| Current study | Sweden 1964-2014 | <18 (median 15) | 9405 (UC,CD) | 148 682 | 497 (any cancer) 122 (CRC) 24 (lymphoid) |
3.3 (3.1 to 3.6)‡ 0.6 (0.4 to 0.9)§ |
HR for any cancer: UC: 2.6 (2.3 to 3.0) CD: 1.7 (1.5 to 2.1) HR for CRC UC: 33 (23 to 49) CD: 5.8 (3.2 to 10) |
CD=Crohn’s disease; CI=confidence interval; CRC=colorectal cancer; HR=Hazard Ratio; NA=Not applicable; NR=not reported; thio=thiopurines; UC=ulcerative colitis.
*Standardised incidence ratio, unless otherwise stated
†Followed up until 23rd birthday
‡All follow-up
§Followed up until 18th birthday