Meta-analysis: colorectal and small bowel cancer risk in patients with Crohn's disease.

TLDR: This study aims to establish a causal relationship between Crohn's disease and small bowel cancer and the risk of colorectal cancer by identifying patients at high risk of both disease and disease progression.

Abstract: Summary Background Crohn's disease is associated with small bowel cancer whilst risk of colorectal cancer is less clear Aim  To ascertain the combined estimates of relative risk of these cancers in Crohn's disease Methods  MEDLINE was searched to identify relevant papers Exploding references identified additional publications When two papers reviewed the same cohort, the later study was used Results  Meta-analysis showed overall colorectal cancer relative risk in Crohn's disease as 25 (13–47), 45 (13–149) for patients with colonic disease and 11 (08–15) in ileal disease Meta-regression showed reduction in relative risk over the past 30 years Subgroup analysis showed Scandinavia had significantly lower colorectal cancer relative risk than the UK and North America Cumulative risk analysis showed 10 years following diagnosis of Crohn's disease relative risk of colorectal cancer is 29% (15%–53%) Meta-analysis showed small bowel cancer relative risk in Crohn's disease is 332 (159–609) Small bowel cancer relative risk has not significantly reduced over the last 30 years Conclusion  Relative risk of colorectal and small bowel cancers are significantly raised in Crohn's disease Cumulative risk of colorectal cancer of 29% at 10 years suggests a potential benefit from routine screening However, the value of screening requires rigorous appraisal