Abstract：
A faecal immunochemical tests (FIT) cut-off of ≥10 μg Hb/g faeces is now recommended in the UK as a gateway to urgent (suspected cancer) investigation for colorectal cancer (CRC), based on an expected CRC risk threshold of 3%.
To quantify the risk of CRC at FIT cut-offs by age, haemoglobin and platelet strata.
A cohort study of a symptomatic CRC pathway based on primary care FIT tests in Nottingham, UK (November 2017-2021) with 1-year follow-up. Heat maps showed the cumulative 1-year CRC risk using Kaplan-Meier estimates.
In total, 514 (1.5%) CRCs were diagnosed following 33,694 index FIT requests. Individuals with a FIT ≥ 10 μg Hb/g faeces had a >3% risk of CRC, except patients under the age of 40 years (CRC risk 1.45% [95% CI: 0.03%-2.86%]). Non-anaemic patients with a FIT < 100 μg Hb/g faeces had a CRC risk of <3%, except those between the age of 70 and 85 years (5.26% 95% CI: 2.72%-7.73%). Using a ≥3% CRC threshold in patients <55 years calculated using FIT, age and anaemia might allow 160-220 colonoscopies per 10,000 FITs to be re-purposed, at a cost of missing 1-2 CRCs.
FIT alone with a single cut-off is unlikely to be a panacea for optimising CRC diagnosis, as risk varies by FIT, age and anaemia when faecal haemoglobin levels are below 100 μg Hb/g. Tailored FIT cut-offs for investigation on a CRC pathway could reduce the number of investigations needed at a 3% CRC risk threshold.
To quantify the risk of CRC at FIT cut-offs by age, haemoglobin and platelet strata.
A cohort study of a symptomatic CRC pathway based on primary care FIT tests in Nottingham, UK (November 2017-2021) with 1-year follow-up. Heat maps showed the cumulative 1-year CRC risk using Kaplan-Meier estimates.
In total, 514 (1.5%) CRCs were diagnosed following 33,694 index FIT requests. Individuals with a FIT ≥ 10 μg Hb/g faeces had a >3% risk of CRC, except patients under the age of 40 years (CRC risk 1.45% [95% CI: 0.03%-2.86%]). Non-anaemic patients with a FIT < 100 μg Hb/g faeces had a CRC risk of <3%, except those between the age of 70 and 85 years (5.26% 95% CI: 2.72%-7.73%). Using a ≥3% CRC threshold in patients <55 years calculated using FIT, age and anaemia might allow 160-220 colonoscopies per 10,000 FITs to be re-purposed, at a cost of missing 1-2 CRCs.
FIT alone with a single cut-off is unlikely to be a panacea for optimising CRC diagnosis, as risk varies by FIT, age and anaemia when faecal haemoglobin levels are below 100 μg Hb/g. Tailored FIT cut-offs for investigation on a CRC pathway could reduce the number of investigations needed at a 3% CRC risk threshold.
摘要：
现在，英国建议将粪便免疫化学试验（FIT）的截止值≥10μgHb/g粪便作为结直肠癌（CRC）紧急（疑似癌症）调查的门户。基于3%的预期CRC风险阈值。
按年龄量化FIT截止时CRC的风险，血红蛋白和血小板层。
一项基于诺丁汉初级保健FIT测试的有症状CRC途径的队列研究，英国（2017年11月-2021年），为期1年的随访。热图显示了使用Kaplan-Meier估计的累积1年CRC风险。
总共，在33,694个索引FIT请求后，诊断出514个（1.5%）CRC。FIT≥10μgHb/g粪便的个体患CRC的风险>3%，40岁以下患者除外（CRC风险1.45%[95%CI：0.03%-2.86%]）。FIT<100μgHb/g粪便的非贫血患者的CRC风险<3％，年龄在70岁至85岁之间的人群除外(5.26%95%CI:2.72%-7.73%)。在使用FIT计算的<55岁患者中使用≥3%的CRC阈值，年龄和贫血可能允许每10,000个FIT进行160-220个结肠镜检查，以缺少1-2个CRC为代价。
单独使用FIT与单个截止值不太可能成为优化CRC诊断的灵丹妙药。由于风险因FIT而异，当粪便血红蛋白水平低于100μgHb/g时，年龄和贫血。针对CRC途径的调查量身定制的FIT截止值可以减少在3％CRC风险阈值下所需的调查数量。
按年龄量化FIT截止时CRC的风险，血红蛋白和血小板层。
一项基于诺丁汉初级保健FIT测试的有症状CRC途径的队列研究，英国（2017年11月-2021年），为期1年的随访。热图显示了使用Kaplan-Meier估计的累积1年CRC风险。
总共，在33,694个索引FIT请求后，诊断出514个（1.5%）CRC。FIT≥10μgHb/g粪便的个体患CRC的风险>3%，40岁以下患者除外（CRC风险1.45%[95%CI：0.03%-2.86%]）。FIT<100μgHb/g粪便的非贫血患者的CRC风险<3％，年龄在70岁至85岁之间的人群除外(5.26%95%CI:2.72%-7.73%)。在使用FIT计算的<55岁患者中使用≥3%的CRC阈值，年龄和贫血可能允许每10,000个FIT进行160-220个结肠镜检查，以缺少1-2个CRC为代价。
单独使用FIT与单个截止值不太可能成为优化CRC诊断的灵丹妙药。由于风险因FIT而异，当粪便血红蛋白水平低于100μgHb/g时，年龄和贫血。针对CRC途径的调查量身定制的FIT截止值可以减少在3％CRC风险阈值下所需的调查数量。
