Lei Ian Io, O'Connell Nicola, Adu-Darko Michael Agyekum, Parambil Jessiya, Suresh Vishnupriya, Mc Donnell Kiara, Newville Jessie, Chaplin Kirsten, Siyambalapityage Deekshi, Khan Asad, Muhammad Usman, Emil John, Abbas Merali, Kanji Zia, Khalil Omar, Alam Hamza, Bennett Amelia, Soanes Hannah, Bhattacharyya Adrija, Frey Karl, Meakins Rosie, Singhal Archit, Pack George, Gerrits Melike, Paterson Harry, Cheung Vincent, Cullen Sue, Aslam Imran, Shekhar Chander, Arasaradnam Ramesh P
Institute of Precision Diagnostics & Translational Medicine, University Hospital of Coventry and Warwickshire, Clifford Bridge Rd, Coventry CV2 2DX, UK.
Warwick Medical School, University of Warwick, Coventry CV4 7AL, UK.
Cancers (Basel). 2025 Jun 11;17(12):1951. doi: 10.3390/cancers17121951.
Colon capsule endoscopy (CCE) or panenteric capsule endoscopy (PCE) offers a promising, non-invasive diagnostic approach for patients with iron deficiency anaemia (IDA). However, high rates of conversion to conventional colonoscopy (CCC) following capsule procedures reduce cost-effectiveness and patient satisfaction. Optimising the faecal immunochemical test (FIT) threshold may improve patient stratification and reduce unnecessary conversions in future applications within the IDA diagnostic pathway. The CLEAR IDA study was a multicentre, retrospective observational study conducted across four UK hospitals. Data were collected over a six-month study period and included patients referred via the two-week-wait (2WW) cancer pathway for iron deficiency, with or without anaemia, over a 12-month timeframe. Colonoscopy findings were analysed and extrapolated using NHS England's CCE-to-colonoscopy referral criteria to assess the predictive value of FIT for colorectal cancer (CRC), polyp burden, and CCC using ROC curve analysis. The optimal FIT threshold was identified through three complementary approaches: threshold-based analysis, decision curve analysis, and cost-benefit modelling. A total of 1531 patients were analysed; only 1.6% underwent small bowel capsule endoscopy. The diagnostic accuracy (AUC) of FIT for predicting CRC, polypoidal lesions, and CCC was 0.78, 0.58, and 0.69, respectively. Threshold-based analysis identified FIT = 15 µg/g as the lowest level at which CCC rates significantly increased ( = 0.02; OR = 1.87; 95% CI: 1.07-3.14). Decision curve analysis showed a maximum net benefit at FIT = 17.6 µg/g, while cost-benefit modelling identified 9 µg/g as the most cost-effective. Raising the threshold to 10 µg/g resulted in a net loss of GBP -294.4 per patient. An optimal cost-effective FIT threshold range was identified between 10 and 17.6 µg/g. The threshold selection should be tailored to local service capacity and resource availability. While FIT alone is an imperfect triage tool, optimising thresholds between 10 and 17 µg/g may enhance cost-effectiveness and guide appropriate PCE use in IDA.
结肠胶囊内镜检查（CCE）或全肠胶囊内镜检查（PCE）为缺铁性贫血（IDA）患者提供了一种有前景的非侵入性诊断方法。然而，胶囊检查后常规结肠镜检查（CCC）的转化率较高，降低了成本效益和患者满意度。优化粪便免疫化学检测（FIT）阈值可能会改善患者分层，并在IDA诊断途径的未来应用中减少不必要的转换。CLEAR IDA研究是一项在英国四家医院进行的多中心回顾性观察研究。在为期六个月的研究期间收集数据，包括在12个月时间范围内通过两周等待（2WW）癌症途径转诊的缺铁患者，无论有无贫血。使用英国国民保健制度（NHS）英格兰的CCE转结肠镜检查转诊标准对结肠镜检查结果进行分析和推断，以通过ROC曲线分析评估FIT对结直肠癌（CRC）、息肉负担和CCC的预测价值。通过三种互补方法确定最佳FIT阈值：基于阈值的分析、决策曲线分析和成本效益建模。共分析了1531例患者；仅1.6%的患者接受了小肠胶囊内镜检查。FIT预测CRC、息肉样病变和CCC的诊断准确性（AUC）分别为0.78、0.58和0.69。基于阈值的分析确定FIT = 15 µg/g是CCC发生率显著增加的最低水平（P = 0.02；OR = 1.87；95% CI：1.07 - 3.14）。决策曲线分析显示FIT = 17.6 µg/g时净效益最大，而成本效益建模确定9 µg/g为最具成本效益。将阈值提高到10 µg/g导致每位患者净损失294.4英镑。确定了10至17.6 µg/g之间的最佳成本效益FIT阈值范围。阈值选择应根据当地服务能力和资源可用性进行调整。虽然单独的FIT是一种不完善的分诊工具，但在10至17 µg/g之间优化阈值可能会提高成本效益，并指导IDA患者适当使用PCE。
