Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
Clinical Effectiveness Research Group, Department of Transplantation Medicine, Oslo University Hospital, Oslo, Norway; Clinical Effectiveness Group, Institute of Health and Society, University of Oslo, Oslo, Norway.
Ann Oncol. 2022 Jun;33(6):649-656. doi: 10.1016/j.annonc.2022.02.226. Epub 2022 Mar 8.
Uncertainty prevails about the magnitude of excess risk of small bowel cancer in patients with inflammatory bowel disease (IBD).
To quantify the risk of small bowel adenocarcinoma and neuroendocrine tumors in patients with ulcerative colitis (UC) and Crohn's disease (CD), we undertook a population-based cohort study of all patients with IBD diagnosed in Norway and Sweden from 1987 to 2016. Patients were followed through linkage to national registers. We calculated standardized incidence ratios (SIRs) with 95% confidence intervals (CIs) of small bowel adenocarcinomas and neuroendocrine tumors for patients with CD and UC. We excluded the first year of follow-up to reduce reverse causality.
Among 142 008 patients with a median follow-up of 10.0 years, we identified 66 adenocarcinomas and 57 neuroendocrine tumors in the small bowel. The SIR of small bowel adenocarcinoma was 8.3 (95% CI 5.9-11.3) in CD and 2.0 (95% CI 1.2-3.1) in UC. The incidence rates of adenocarcinomas were highest in CD with stricturing disease and extent limited to the small bowel, at 14.7 (95% CI 8.2-24.2) and 15.8 (95% CI 8.4-27.0) per 100 000 person-years, respectively. The SIR of neuroendocrine tumors was 2.5 (95% CI 1.5-3.9) in CD and 2.0 (95% CI 1.4-2.8) in UC.
Patients with CD experienced an eightfold increased risk of small bowel adenocarcinomas, patients with both UC and CD experienced an about twofold increased risk of neuroendocrine tumors, and patients with UC experienced a twofold increased risk of small bowel adenocarcinoma. The small absolute excess cancer risk suggests that active surveillance to diagnose small intestinal cancer early is unlikely to be cost-effective.
炎症性肠病（IBD）患者发生小肠癌的风险程度尚不确定。
为了量化溃疡性结肠炎（UC）和克罗恩病（CD）患者发生小肠腺癌和神经内分泌肿瘤的风险，我们对 1987 年至 2016 年期间在挪威和瑞典诊断为 IBD 的所有患者进行了一项基于人群的队列研究。通过与国家登记册的链接对患者进行随访。我们计算了 CD 和 UC 患者小肠腺癌和神经内分泌肿瘤的标准化发病比（SIR）及其 95%置信区间（CI）。我们排除了随访的前 1 年，以减少反向因果关系。
在 142008 名中位随访时间为 10.0 年的患者中，我们在小肠中发现了 66 例腺癌和 57 例神经内分泌肿瘤。CD 患者的小肠腺癌 SIR 为 8.3（95%CI 5.9-11.3），UC 患者为 2.0（95%CI 1.2-3.1）。在局限于小肠且狭窄疾病程度严重的 CD 患者中，腺癌的发生率最高，分别为 14.7（95%CI 8.2-24.2）和 15.8（95%CI 8.4-27.0）/100000 人年。CD 患者的神经内分泌肿瘤 SIR 为 2.5（95%CI 1.5-3.9），UC 患者为 2.0（95%CI 1.4-2.8）。
CD 患者小肠腺癌的风险增加了 8 倍，UC 和 CD 患者神经内分泌肿瘤的风险增加了约 2 倍，UC 患者小肠腺癌的风险增加了 2 倍。较小的绝对癌症风险表明，积极监测以早期诊断小肠癌不太可能具有成本效益。
