Department of Gastroenterology, Complexo Hospitalario Universitario de Ourense, Ourense 32005, Spain.
World J Gastroenterol. 2019 May 21;25(19):2383-2401. doi: 10.3748/wjg.v25.i19.2383.
The quantitative faecal immunochemical test for haemoglobin (FIT) has been revealed to be highly accurate for colorectal cancer (CRC) detection not only in a screening setting, but also in the assessment of patients presenting lower bowel symptoms. Therefore, the National Institute for Health and Care Excellence has recommended the adoption of FIT in primary care to guide referral for suspected CRC in low-risk symptomatic patients using a 10 µg Hb/g faeces threshold. Nevertheless, it is unknown whether FIT´s accuracy remains stable throughout the broad spectrum of possible symptoms.
To perform a systematic review and meta-analysis to assess FIT accuracy for CRC detection in different clinical settings.
A systematic literature search was performed using MEDLINE and EMBASE databases from inception to May 2018 to conduct a meta-analysis of prospective studies including symptomatic patients that evaluated the diagnostic accuracy of quantitative FIT for CRC detection. Studies were classified on the basis of brand, threshold of faecal haemoglobin concentration for a positive test result, percentage of reported symptoms (solely symptomatic, mixed cohorts) and CRC prevalence (< 2.5%, ≥ 2.5%) to limit heterogeneity and perform subgroup analysis to assess the influence of clinical spectrum on FIT´s accuracy to detect CRC.
Fifteen cohorts including 13073 patients (CRC prevalence 0.4% to 16.8%) were identified. Pooled estimates of sensitivity for studies using OC-Sensor at 10 µg Hb/g faeces threshold ( = 10400) was 89.6% [95% confidence interval (CI): 82.7% to 94.0%). However, pooled estimates of sensitivity for studies formed solely by symptomatic patients ( = 4035) and mixed cohorts ( = 6365) were 94.1% (95%CI: 90.0% to 96.6%) and 85.5% (95%CI: 76.5% to 91.4%) respectively ( < 0.01), while there were no statistically significant differences between pooled sensitivity of studies with CRC prevalence < 2.5% (84.9%, 95%CI: 73.4% to 92.0%) and ≥ 2.5% (91.7%, 95%CI: 83.3% to 96.1%) ( = 0.25). At the same threshold, OC-Sensor sensitivity to rule out any significant colonic lesion was 78.6% (95%CI: 75.6% to 81.4%). We found substantial heterogeneity especially when assessing specificity.
The results of this meta-analysis confirm that, regardless of CRC prevalence, quantitative FIT is highly sensitive for CRC detection. However, FIT ability to rule out CRC is higher in studies solely including symptomatic patients.
定量粪便免疫化学检测血红蛋白（FIT）不仅在筛查环境中，而且在评估出现下消化道症状的患者时，均被证实对结直肠癌（CRC）的检测具有高度准确性。因此，英国国家卫生与保健优化研究所建议在初级保健中采用 FIT，以便使用 10μg Hb/g 粪便的阈值来指导疑似 CRC 低风险有症状患者的转诊。然而，FIT 的准确性是否在广泛的可能症状范围内保持稳定仍不得而知。
进行系统评价和荟萃分析，以评估不同临床环境下 FIT 检测 CRC 的准确性。
使用 MEDLINE 和 EMBASE 数据库从创建到 2018 年 5 月进行系统文献检索，对评估定量 FIT 检测 CRC 准确性的前瞻性研究进行荟萃分析。研究根据品牌、粪便血红蛋白浓度阳性检测结果的阈值、报告症状的百分比（单纯症状、混合队列）和 CRC 患病率（<2.5%，≥2.5%）进行分类，以限制异质性并进行亚组分析，以评估临床谱对 FIT 检测 CRC 准确性的影响。
共确定了 15 个队列，包括 13073 名患者（CRC 患病率为 0.4%至 16.8%）。使用 OC-Sensor 在 10μg Hb/g 粪便阈值时的汇总敏感性估计值为 89.6%（95%置信区间：82.7%至 94.0%）。然而，仅由有症状患者组成的研究（ = 4035）和混合队列（ = 6365）的汇总敏感性估计值分别为 94.1%（95%CI：90.0%至 96.6%）和 85.5%（95%CI：76.5%至 91.4%）（<0.01），而 CRC 患病率<2.5%（84.9%，95%CI：73.4%至 92.0%）和≥2.5%（91.7%，95%CI：83.3%至 96.1%）的研究之间的汇总敏感性没有统计学差异（ = 0.25）。在同一阈值下，OC-Sensor 排除任何显著结直肠病变的敏感性为 78.6%（95%CI：75.6%至 81.4%）。我们发现了很大的异质性，尤其是在评估特异性时。
这项荟萃分析的结果证实，无论 CRC 患病率如何，定量 FIT 对 CRC 的检测均具有高度敏感性。然而，FIT 排除 CRC 的能力在仅包括有症状患者的研究中更高。
