Combining the quantitative faecal immunochemical test and full blood count reliably rules out colorectal cancer in a symptomatic patient referral pathway

Abstract Purpose Faecal Immunochemical Test (FIT) has proven utility for Colorectal Cancer (CRC) detection in symptomatic patients. Most studies have examined FIT in symptomatic patients subsequently referred from primary care. We investigated associations between CRC and FIT in both referred and non-referred symptomatic patients. Methods A retrospective, observational study of all patients with a FIT submitted Aug 2018 to Jan 2019 in NHS GG&C was performed. Referral to colorectal/gastroenterology and decision to perform colonoscopy were recorded. FIT results were grouped as f-Hb < 10/10–149/150–399/ ≥ 400 μg/g. The MCN cancer registry identified new cases of CRC. Covariables were compared using the χ2 test. Multivariate binary logistic regression identified independent predictors of CRC. Results A total of 4968 patients were included. Raised FIT correlated with decision to refer (p < 0.001) and scope (p < 0.001). With 23-month median follow-up, 61 patients were diagnosed with CRC. These patients were older (median 69 vs 59 years, cancer and no cancer respectively, p = 0.001), more likely to be male (55.7% vs 42.1%, p = 0.033), and to report rectal bleeding (51.7% vs 36.1%, p = 0.013). FIT (< 10 µg/g 8.2% vs 76.7% and ≥ 400 µg/g 55.7% vs 3.8%, p < 0.001) and anaemia (45.9% vs 19.7%, p < 0.001) were associated with CRC. On multivariate analysis, age (p = 0.023), male sex (p = 0.04), FIT (≥ 400 OR 54.256 (95% CI:20.683–142.325; p < 0.001)), and anaemia (OR 1.956 (1.071–3.574; p = 0.029)) independently predicted CRC. One patient (0.04%) with a negative FIT and normal haemoglobin had CRC. Conclusion GP referral and secondary care investigation patterns were influenced by FIT. The combination of normal Hb and f-Hb excluded CRC in 99.96% of cases, providing excellent reassurance to those prioritising access to endoscopy services.

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Choice of faecal immunochemical test matters: comparison of OC-Sensor and HM-JACKarc, in the assessment of patients at high risk of colorectal cancer

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2020-1170 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Caroline J. Chapman ◽

Ayan Banerjea ◽

David J Humes ◽

Jaren Allen ◽

Simon Oliver ◽

...

Keyword(s):

Colorectal Cancer ◽

Clinical Decision Making ◽

Full Range ◽

Clinical Decision ◽

Detection Rates ◽

Faecal Immunochemical Test ◽

Specimen Collection ◽

Increased Risk ◽

Immunochemical Test

AbstractObjectivesCurrently, NICE recommends the use of faecal immunochemical test (FIT) at faecal haemoglobin concentrations (f-Hb) of 10 μg Hb/g faeces to stratify for colorectal cancer (CRC) risk in symptomatic populations. This f-Hb cut-off is advised across all analysers, despite the fact that a direct comparison of analyser performance, in a clinical setting, has not been performed.MethodsTwo specimen collection devices (OC-Sensor, OC-S; HM-JACKarc, HM-J) were sent to 914 consecutive individuals referred for follow up due to their increased risk of CRC. Agreement of f-Hb around cut-offs of 4, 10 and 150 µg Hb/g faeces and CRC detection rates were assessed. Two OC-S devices were sent to a further 114 individuals, for within test comparisons.ResultsA total of 732 (80.1%) individuals correctly completed and returned two different FIT devices, with 38 (5.2%) CRCs detected. Median f-Hb for individuals diagnosed with and without CRC were 258.5 and 1.8 µg Hb/g faeces for OC-S and 318.1 and 1.0 µg Hb/g faeces for HM-J respectively. Correlation of f-Hb results between OC-S/HM-J over the full range was rho=0.74, p<0.001. Using a f-Hb of 4 µg Hb/g faeces for both tests found an agreement of 88.1%, at 10 µg Hb/g faeces 91.7% and at 150 µg Hb/g faeces 96.3%. A total of 114 individuals completed and returned two OC-S devices; correlation across the full range was rho=0.98, p<0.001.ConclusionsWe found large variations in f-Hb when different FIT devices were used, but a smaller variation when the same FIT device was used. Our data suggest that analyser-specific f-Hb cut-offs are applied with regard to clinical decision making, especially at lower f-Hb.

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Do socioeconomic factors play a role in nonadherence to follow-up colonoscopy after a positive faecal immunochemical test in the Flemish colorectal cancer screening programme?

European Journal of Cancer Prevention ◽

10.1097/cej.0000000000000533 ◽

2020 ◽

Vol 29 (2) ◽

pp. 119-126 ◽

Cited By ~ 1

Author(s):

S. Hoeck ◽

W. van de Veerdonk ◽

I. De Brabander

Keyword(s):

Colorectal Cancer ◽

Cancer Screening ◽

Socioeconomic Factors ◽

Colorectal Cancer Screening ◽

Screening Programme ◽

Faecal Immunochemical Test ◽

Cancer Screening Programme ◽

Immunochemical Test

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EXPRESS: Faecal haemoglobin concentration thresholds for reassurance and urgent investigation for colorectal cancer based on a faecal immunochemical test (FIT) in symptomatic patients in primary care.

Annals of Clinical Biochemistry International Journal of Laboratory Medicine ◽

10.1177/0004563220985547 ◽

2020 ◽

pp. 000456322098554

Author(s):

Craig Mowat ◽

Jayne Digby ◽

Judith A Strachan ◽

Rebecca Katherine McCann ◽

Francis A Carey ◽

...

Keyword(s):

Colorectal Cancer ◽

Primary Care ◽

Gastrointestinal Disease ◽

Haemoglobin Concentration ◽

Individual Risk ◽

First Year ◽

Faecal Immunochemical Test ◽

Persistent Symptoms ◽

Immunochemical Test ◽

Hb Concentration

Background Faecal haemoglobin concentration (f-Hb), estimated using a faecal immunochemical test (FIT), can be safely implemented in primary care to assess risk of colorectal cancer (CRC). Clinical outcomes of patients presenting with symptoms of lower gastrointestinal disease were examined using an extensive range of f-Hb thresholds to decide on reassurance or referral for further investigation. Methods All patients who attended primary care and submitted a single faecal specimen FIT in the first year of the routine service had f-Hb estimated using HM-JACKarc: f-Hb thresholds from <2 to > 400 Âµg Hb/g faeces (Âµg/g) were examined. Results Low f-Hb thresholds of <2, <7, <10 and <20 Âµg/g gave respective CRC risks of 0.1, 0.3, 0.3 and 0.4%, numbers needed to scope (NNS) for one CRC of 871, 335, 300 and 249, and âfalse negativeâ rates of 2.9, 11.4, 13.3 and 17.1%. With thresholds of <2, <7, <10, and <20 Âµg/g, 48.6, 74.6, 78.1 and 83.2% respectively of symptomatic patients could be managed without further investigation. With reassurance thresholds of <2 Âµg/g, <7 Âµg/g and <10 Âµg/g, the thresholds for referral for urgent investigation would be >400 Âµg/g, >200 Âµg/g and >100 Âµg/g. However, patients with a f-Hb concentration of <10 or <20 Âµg/g with iron deficiency anaemia, or with severe or persistent symptoms, should not be denied further investigation. Conclusions In primary care, f-Hb, in conjunction with clinical assessment, can safely and objectively determine individual risk of CRC and decide on simple reassurance or urgent, or routine referral.

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Diagnostic performance of a faecal immunochemical test for patients with low-risk symptoms of colorectal cancer in primary care: an evaluation in the South West of England

British Journal of Cancer ◽

10.1038/s41416-020-01221-9 ◽

2021 ◽

Author(s):

Sarah E. R. Bailey ◽

Gary A. Abel ◽

Alex Atkins ◽

Rachel Byford ◽

Sarah-Jane Davies ◽

...

Keyword(s):

Colorectal Cancer ◽

Primary Care ◽

Predictive Value ◽

Low Risk ◽

The South ◽

Faecal Immunochemical Test ◽

Urgent Referral ◽

South West ◽

Immunochemical Test ◽

Risk Of Cancer

Abstract Background The faecal immunochemical test (FIT) was introduced to triage patients with low-risk symptoms of possible colorectal cancer in English primary care in 2017, underpinned by little primary care evidence. Methods All healthcare providers in the South West of England (population 4 million) participated in this evaluation. 3890 patients aged ≥50 years presenting in primary care with low-risk symptoms of colorectal cancer had a FIT from 01/06/2018 to 31/12/2018. A threshold of 10 μg Hb/g faeces defined a positive test. Results Six hundred and eighteen (15.9%) patients tested positive; 458 (74.1%) had an urgent referral to specialist lower gastrointestinal (GI) services within three months. Forty-three were diagnosed with colorectal cancer within 12 months. 3272 tested negative; 324 (9.9%) had an urgent referral within three months. Eight were diagnosed with colorectal cancer within 12 months. Positive predictive value was 7.0% (95% CI 5.1–9.3%). Negative predictive value was 99.8% (CI 99.5–99.9%). Sensitivity was 84.3% (CI 71.4–93.0%), specificity 85.0% (CI 83.8–86.1%). The area under the ROC curve was 0.92 (CI 0.86–0.96). A threshold of 37 μg Hb/g faeces would identify patients with an individual 3% risk of cancer. Conclusions FIT performs exceptionally well to triage patients with low-risk symptoms of colorectal cancer in primary care; a higher threshold may be appropriate in the wake of the COVID-19 crisis.

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Diagnostic performance of the faecal immunochemical test for patients with low-risk symptoms of colorectal cancer in primary care: a service evaluation in the South West of England

10.1101/2020.08.21.20173534 ◽

2020 ◽

Cited By ~ 1

Author(s):

Sarah ER Bailey ◽

Gary A Abel ◽

Alex Atkins ◽

Rachel Byford ◽

Sarah-Jane Davies ◽

...

Keyword(s):

Colorectal Cancer ◽

Primary Care ◽

Predictive Value ◽

Secondary Care ◽

Diagnostic Performance ◽

Low Risk ◽

Faecal Immunochemical Test ◽

South West ◽

Immunochemical Test ◽

Risk Of Cancer

Objectives To evaluate the faecal immunochemical test (FIT) for primary care clinicians to triage patients with low-risk symptoms of possible colorectal cancer, and to estimate its diagnostic performance. Design Service delivery evaluation. Setting All primary and secondary care providers in the South West of England, approximate population 4 million. Participants 3890 patients aged ≥50 years presenting in primary care with low-risk symptoms of colorectal cancer, following NICE NG12 and DG30, with a FIT (HM-JACKarc assay) analysed from 01/06/2018 to 31/12/2018. Main outcome measures Diagnosis of colorectal cancer. Results 618 (15.9%) patients tested positive at a threshold of 10μg Hb/g faeces (median 36μg Hb/g faeces (IQR 17 to 149)); 458 (74.1%) of these had an urgent referral to specialist lower gastrointestinal (GI) services within three months. 43 were diagnosed with colorectal cancer within 12 months. 3272 patients tested negative; 324 (9.9%) were referred on an urgent lower GI pathway in secondary care within three months. 8 were diagnosed with colorectal cancer within 12 months. The positive predictive value of FIT for colorectal cancer in the low-risk symptomatic population was 7.0% (95% CI 5.1% to 9.3%) and the negative predictive value was 99.8% (CI 99.5% to 99.9%). Sensitivity was 84.3% (CI 71.4% to 93.0%), and specificity 85.0% (CI 83.8% to 86.1%). The area under the ROC curve was 0.92 (CI 0.86 to 0.96). A threshold of 37μg Hb/g faeces would identify patients with an individual 3% risk of cancer. Conclusions FIT performs exceptionally well to triage patients with low-risk symptoms of colorectal cancer in primary care. The threshold value of 10μg Hb/g faeces represents a risk of cancer below 3% used in current NICE guidance; however, this lower value may be appropriate to meet the national aspiration of improving cancer diagnostics.

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