Department of Gastroenterology, North Zealand University Hospital, Frederikssund, Denmark.
Department of Obstetrics and Gynaecology, North Zealand University Hospital, Hillerød, Denmark.
Inflamm Bowel Dis. 2021 Oct 20;27(11):1795-1803. doi: 10.1093/ibd/izaa340.
The risk of colorectal cancer (CRC) for patients with inflammatory bowel disease (IBD) has previously been investigated with conflicting results. We aimed to investigate the incidence and risk of CRC in IBD, focusing on its modification by treatment.
All patients with incident IBD (n = 35,908) recorded in the Danish National Patient Register between 1997 and 2015 (ulcerative colitis: n = 24,102; Crohn's disease: n = 9739; IBD unclassified: n = 2067) were matched to approximately 50 reference individuals (n = 1,688,877). CRC occurring after the index date was captured from the Danish Cancer Registry. Exposure to medical treatment was divided into categories including none, systemic 5-aminosalicylates, immunomodulators, and biologic treatment. The association between IBD and subsequent CRC was investigated by Cox regression and Kaplan-Meier estimates.
Of the IBD patients, 330 were diagnosed with CRC, resulting in a hazard ratio (HR) of 1.15 (95% confidence interval [CI], 1.03-1.28) as compared with the reference individuals. However, when excluding patients diagnosed with CRC within 6 months of their IBD diagnosis, the HR decreased to 0.80 (95% CI, 0.71-0.92). Patients with ulcerative colitis receiving any medical treatment were at significantly higher risk of developing CRC than patients with ulcerative colitis who were not given medical treatment (HR, 1.35; 95% CI, 1.01-1.81), whereas a similar effect of medical treatment was not observed in patients with Crohn's disease or IBD unclassified.
Medical treatment does not appear to affect the risk of CRC in patients with IBD. The overall risk of developing CRC is significantly increased in patients with IBD as compared with the general population. However, when excluding patients diagnosed with CRC within 6 months of their IBD diagnosis, the elevated risk disappears.
结直肠癌（CRC）的风险在炎症性肠病（IBD）患者中已有研究，但结果相互矛盾。本研究旨在探讨 IBD 患者 CRC 的发病率和风险，并重点研究治疗对其的影响。
1997 年至 2015 年期间，丹麦国家患者登记处（登记了 35908 例新发 IBD 患者，溃疡性结肠炎：24102 例；克罗恩病：9739 例；IBD 未分类：2067 例）记录了所有 IBD 患者，并将其与大约 50 名对照个体（1688877 人）进行匹配。通过丹麦癌症登记处获取索引日期后发生的 CRC。将药物暴露分为无治疗、全身 5-氨基水杨酸、免疫调节剂和生物治疗。采用 Cox 回归和 Kaplan-Meier 估计来研究 IBD 与随后发生 CRC 的相关性。
在 IBD 患者中，有 330 例被诊断为 CRC，其风险比（HR）为 1.15（95%置信区间[CI]，1.03-1.28），与对照个体相比。然而，当排除 IBD 诊断后 6 个月内被诊断为 CRC 的患者后，HR 降至 0.80（95%CI，0.71-0.92）。与未接受药物治疗的溃疡性结肠炎患者相比，接受任何药物治疗的溃疡性结肠炎患者发生 CRC 的风险显著更高（HR，1.35；95%CI，1.01-1.81），而克罗恩病或 IBD 未分类患者中未观察到药物治疗的类似效果。
药物治疗似乎不会影响 IBD 患者发生 CRC 的风险。与普通人群相比，IBD 患者发生 CRC 的总体风险显著增加。然而，当排除 IBD 诊断后 6 个月内被诊断为 CRC 的患者后，这种升高的风险消失。
