Table 1.
Studies of lymphoma risk in inflammatory bowel disease (IBD)
| Author, year | IBD | No of subjects | Lymphomas | Relative risk (95% CI) |
| Lewis1 2001 | CD | 6605 | 7 | 1.6 (0.6–3.3) |
| Arseneau2 2001 | CD | 5426 | 21 | 2.0 (1.3–3.1) |
| Bernstein3 2001 | CD | 2857 | 9 | 2.4 (1.2–5.0) |
| Mellemkjaer37 2000 | CD | 2645 | 6 | 1.4 (0.6–1.3) |
| Palli38 1998 | CD | 231 | 1 | 10 |
| Loftus6 2000 | CD | 216 | 4 | 2.4 (0.1–13) |
| Persson7 1994 | CD | 1251 | 4 | 1.3 (0.4–3.4) |
| Munkholm8 1993 | CD | 373 | 0 | 0.0 |
| Ekbom12 1991 | CD | 1655 | 1 | 0.4 (0.0–2.4) |
| Gyde10 1980 | CD | 513 | 1 | 1.0 |
| Lewis1 2001 | UC | 10391 | 11 | 1.1 (0.5–2.2) |
| Bernstein3 2001 | UC | 2672 | 7 | 1.0 (0.5–2.2) |
| Palli5 2000 | UC | 689 | 6 | 4.2 |
| Loftus6 2000 | UC | 238 | 0 | 0.0 (0.0–6.4) |
| Karlén11 1999 | UC | 1547 | 3 | 1.2 (0.3–2.5) |
| Mellemkjaer4 1995 | UC | 5546 | 7 | 1.4 (0.5–1.3) |
| Ekbom12 1991 | UC | 3121 | 8 | 1.2 (0.5–2.4) |
| Madjlessi28 1986 | UC | 1248 | 3 | 3.4 (0.7–10) |
| Prior9 1982 | UC | 676 | 3 | 2.0 |
| Farrell14 2000 | NS | 782 | 4 | 31 (2.0–64) |
| Masel15 2000 | NS | 4791 | 5 | 6.7 |
| Connell16 1994 | NS | 755 | 0 | 0.0 |
| Greenstein17 1985 | NS | 1961 | 8 | 6.1 |
| All studies above | 122 | 1.8 |
CD, Crohn’s disease; UC, ulcerative colitis; NS, not specified; 95% CI, 95% confidence interval.