Zamani, Mohammad

Summary Background There are inconsistencies in the results of the studies investigating the association between inflammatory bowel disease (IBD) and lymphoma. Aims The aim of this study is to systematically appraise the risk of lymphoma development in patients with IBD. Methods We searched Embase, PubMed and Scopus from inception to 30 April 2024 to identify population‐based cohort studies that evaluated the risk of lymphoma in patients with IBD in comparison with those without IBD. We carried out random‐effects meta‐analyses and estimated pooled relative risks (RRs) with 95% confidence intervals (CIs). Results We identified 23 eligible studies reporting 2078 lymphoma events in 656,731 patients with IBD. Patients with IBD had 30% higher odds of lymphoma (RR = 1.30 [95% CI: 1.21–1.40]). The risk of developing both Hodgkin's lymphoma (nine studies, RR = 1.29 [95% CI: 1.06–1.53]) and non‐Hodgkin's lymphoma (16 studies, RR = 1.31 [95% CI: 1.20–1.42]) was increased in patients with IBD (p for interaction = 0.881). The increased risk of lymphoma was observed in both Crohn's disease (17 studies, RR = 1.54 [95% CI: 1.27–1.80]) and ulcerative colitis (20 studies, RR = 1.22 [95% CI: 1.09–1.35]) (p for interaction = 0.026). Meta‐regression demonstrated that mean age of patients, study year, mean study follow‐up duration, and percentages of immunomodulators and biologics use did not influence study outcome. Conclusions The risk of lymphoma is only modestly increased in patients with IBD, with Crohn's disease having a slightly higher risk than ulcerative colitis. In IBD, there appears to be no difference between the risks of Hodgkin's and non‐Hodgkin's lymphoma.

SummaryBackgroundStudies exploring the association between inflammatory bowel disease (IBD) and pancreatic cancer have reported inconsistent results.AimsTo provide a comprehensive overview of the risk of pancreatic cancer development in patients with IBD.MethodsWe searched Embase, PubMed, Scopus and ProQuest from inception to 31 October 2023. We included population‐based cohort studies examining the risk of incident pancreatic cancer in adult patients with IBD compared to the non‐IBD population. We also retrieved Mendelian randomisation (MR) studies investigating the relationship of IBD with pancreatic cancer risk. We conducted random‐effects meta‐analyses and provided pooled relative risks (RRs) with 95% confidence intervals (CIs).ResultsWe included 13 studies. Among 11 cohort studies, the risk of developing pancreatic cancer increased by 79% in patients with IBD (RR = 1.79 [95% CI: 1.16–2.75]; I2 = 95.7%). Patients either with Crohn's disease (RR = 1.42 [95% CI: 1.24–1.63]) or ulcerative colitis (RR = 1.50 [95% CI: 1.17–1.92]) had increased risk (p for interaction = 0.72). The annual incidence of pancreatic cancer potentially attributable to IBD increased by 55 cases (95% CI: 17–103) per million. Two MR studies demonstrated that genetic liability to IBD was associated with an increased risk of pancreatic cancer.ConclusionsOur results suggest a moderate increase in the risk of pancreatic cancer in patients with IBD, which may be further heightened by genetic predisposition to IBD. The increased risk of pancreatic cancer is probably similar in Crohn's disease and ulcerative colitis.