Clinical Biochemistry, Barts Health NHS Trust, London, UK
Surgery, Barts Health NHS Trust, London, UK.
J Clin Pathol. 2024 Jun 19;77(7):495-499. doi: 10.1136/jcp-2022-208459.
Colorectal cancer (CRC) is the fourth most common cancer in the UK. Following National Institute for Health and Care Excellence guidance for faecal immunochemical testing (FIT), we introduced a service for the measurement of faecal haemoglobin (f-Hb) in symptomatic patients. Previously, we evaluated the first 6 months of the service in three local boroughs, here we re-examine the use of FIT, over a similar 6 months in the two successive years.
Patients who had FIT requested in April-September 2020 and 2021 were studied. Results were obtained from the laboratory information systems and matched with the clinical outcomes of those referred via the urgent lower gastrointestinal cancer pathway. Patient demographics, reason for referral, clinical outcome and diagnostic test performance are reported.
In 2020, 4042 samples were analysed and 57 CRC detected. In 2021, 10 508 samples were analysed and 65 CRC detected. Six (4.9%) patients with CRC had f-Hb <10 µg/g, of whom three were anaemic. In 2020, 27.7% of samples were from patients under 50 years; and in 2021, 32.8%. Sensitivity, specificity, positive predictive value and negative predictive value of f-Hb at ≥10 µg/g for CRC were 92.9%, 46.6%, 6.4% and 99.4% in 2020 and 96.9%, 29.9%, 3.2% and 99.8% in 2021.
As currently used in primary care in North East London, specificity of FIT at a cut-off of 10 µg/g is much lower than in published studies and the impact of this on colorectal services needs to be considered.
结直肠癌（CRC）是英国第四大常见癌症。根据国家卫生与保健卓越研究所（NICE）关于粪便免疫化学检测（FIT）的指导意见，我们为有症状的患者引入了粪便血红蛋白（f-Hb）测量服务。此前，我们在三个地方行政区评估了该服务的前 6 个月，在此，我们在随后的两年中，重新检查了在相似的 6 个月内 FIT 的使用情况。
研究了 2020 年 4 月至 9 月和 2021 年请求进行 FIT 的患者。结果从实验室信息系统中获得，并与通过紧急下胃肠道癌症途径转诊的患者的临床结果相匹配。报告了患者的人口统计学特征、转诊原因、临床结果和诊断测试性能。
2020 年分析了 4042 个样本，发现了 57 例 CRC。2021 年分析了 10508 个样本，发现了 65 例 CRC。6 例（4.9%）CRC 患者的 f-Hb<10μg/g，其中 3 例贫血。2020 年，50 岁以下患者的样本占 27.7%；2021 年，这一比例为 32.8%。2020 年和 2021 年 f-Hb≥10μg/g 时，CRC 的敏感性、特异性、阳性预测值和阴性预测值分别为 92.9%、46.6%、6.4%和 99.4%和 96.9%、29.9%、3.2%和 99.8%。
在伦敦东北部的基层医疗中，目前使用的 FIT 截断值为 10μg/g 时，特异性远低于已发表的研究，这对结直肠服务的影响需要加以考虑。
