FIT Symptomatic

GP holding a FIT kit and leaflet towards a patient

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Read about tools and resources that can support GPs to recognise, refer and manage people with suspected bowel cancer. 

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The Faecal Immunochemical Test (FIT) is a type of faecal occult blood test used to detect invisible traces of blood in faeces. FIT is used to guide the management of patients with lower GI symptoms in two key settings*:  

  • It is used to guide the management of patients who present with signs and symptoms in primary care. The test supports GPs to identify which patients should be referred into secondary care or safety netted.
  • FIT is also used as a triage test in secondary care to guide the management of patients who have been referred routinely or on an urgent referral pathway. 

*It is important to check local pathways as they may differ nationally and between the regions.  

The symptomatic thresholds for a positive result are much lower than the thresholds used in national bowel cancer screening programmes. Currently, the symptomatic threshold is 10 µg Hb/g faeces in England, Wales and Northern Ireland and 20 µg Hb/g in Scotland. 

FIT symptomatic resources

There are some key differences in how the Faecal Immunochemical Test (FIT) is used to screen asymptomatic people through the bowel cancer screening programmes, and to investigate symptomatic patients.

Cancer Research UK have developed infographics to highlight the different uses of FIT.

Overview and eligibility of FIT symptomatic

FIT as a primary care test

Across the UK, FIT is primarily used to manage patients with suspected bowel cancer symptoms in primary care. GPs are responsible for requesting a FIT and asking patients who present with lower GI symptoms to complete the test in all UK nations. 

GPs in England should order a test and receive the result in primary care prior to referral, according to NICE guidance (NG12, 2023)  

In Scotland, most GPs can order the test and act upon the results, but in some Health Boards FIT is used after referral to secondary care (Scottish Referral Guidelines (SRG, 2025)). Make sure to check your local pathways. 

Guidance in Wales and Northern Ireland advises GPs to order a FIT either prior to or alongside an urgent referral depending on the symptoms that the patient presents with. See Wales Lower Gastrointestinal Symptomatic Faecal Immunochemical Testing Pathway ‘FIT’ - National Optimal Pathway and Northern Ireland NICaN Lower GI suspected cancer pathway guidance for the recommendations in full. You can also visit ‘An overview of FIT symptomatic guidance in UK nations’ below for more detail on national guidance.

The BSG/ACPGBI has also published UK-wide guidance (2022) to support the implementation of FIT symptomatic in primary care and align nations. It recommends using FIT in nearly all symptomatic patients as a triage tool to help identify which patients should be referred into secondary care.

Key points to remember when using FIT in primary care:

  • FIT is not required for all symptomatic patients. In all UK nations (except for Northern Ireland) those with rectal/anal mass and/or anal ulceration can be referred onto urgent lower GI pathway without a FIT.
  • Patients with a negative FIT result should still be referred if there is clinical concern of bowel cancer*. If other cancers are suspected, consider making a referral through the most appropriate pathway.
  • In this pathway, primary care is responsible for requesting the FIT and acting on the results. This includes referring patients with a positive result for follow-on investigation.
  • Usually, a FIT result is required alongside a referral to inform secondary care prioritisation. However, variation in local pathways may exist.
  • Primary care may be responsible for requesting additional kits (eg if the kit is spoiled or rejected). Local processes will be in place to order these.

*Check local pathways

Patients should not be discharged from the pathway based on a FIT result alone. GPs should safety net patients until symptoms are explained or resolved.

Benefits of using FIT for symptomatic patients in primary care:

  • FIT can be used to aid a GP’s decision to refer into secondary care.
  • Where a FIT result is below the recommended threshold for referral, the result can still be used to inform decisions about subsequent management (including use of further investigations and Advice & Guidance) and decisions about referral. 
  • Patients should be encouraged to contact their GP if symptoms persist, worsen or change after a negative FIT result.
 Is it important to check local pathways as they can vary across localities.

 

FIT as a triage test in secondary care

FIT can be requested by secondary care to guide the management of patients who have been referred into secondary care.

The responsibility for recording and acting on the result generally lies with whoever requested the test. This could have been in primary or secondary care depending on local pathways. Please refer to local guidance as this may vary.

A negative FIT result does not rule out the possibility of cancer. Patients with a negative result should be safety netted until symptoms are explained or resolved.

Benefits of using FIT in secondary care:

  • As in primary care, patients can be prioritised based on their FIT result and symptoms.
  • Patients with a negative FIT result may be held on patient tracking lists (PTL) in secondary care. These patients are therefore less likely to be lost in the system compared to patients in primary care, where patient initiated follow up is more common.
  • The specialist will have responsibility for following up and acting on the FIT result.

It is important to check local pathways as they can vary across localities.

 

The joint BSG/ACPGBI guidance, published in May 2022, aimed to provide a clear strategy for the use of FIT in the diagnostic pathway for colorectal cancer. The guidance provided 23 recommendations that support GPs to use their clinical judgement, practice safety netting, and follow-up with patients who do not return their FIT sample. 

The BSG/ACPGBI guidance makes several key recommendations:

  • BSG advises using FIT in primary care to select and prioritise patients presenting with potential symptoms of colorectal cancer for further investigation.
  • It advises that almost all patients displaying colorectal cancer signs and symptoms should be given a FIT. The exceptions are to this are patients with an anal/rectal mass and ulceration, who should be referred to secondary care without a FIT result.
  • Where patients have not returned a FIT kit, BSG advises clinicians to:
    • Encourage patients to return a sample or provide them with a new test if the kit has been lost or completed incorrectly.
    • Inform patients who refuse to return a FIT test that their symptoms have not been fully investigated and encourage them to complete the test.
    • Use existing national and local guidelines to assess the risk of colorectal cancer where no FIT result can be obtained. This applies to people who do not, and those who are unable to, complete and return their kit.

NICE guidance, Wales National Optimal Pathway and SRG guidance has since been updated to reflect this guidance.

NICE guidance recommends quantitative Faecal Immunochemical Testing (FIT) using HM‑JACKarc or OC‑Sensor to guide referral for suspected colorectal cancer in adults:

With an abdominal mass, or with a change in bowel habit, or with iron-deficiency anaemia, or those:

  • aged 40 and over with unexplained weight loss and abdominal pain
  • aged under 50 with rectal bleeding and either of the following unexplained symptoms: abdominal pain, weight loss
  • aged 50 and over with any of the following unexplained symptoms: rectal bleeding, abdominal pain, weight loss
  • aged 60 and over with anaemia even in the absence of iron deficiency.

For those with a rectal mass, an unexplained anal mass or unexplained anal ulceration do not need to be offered FIT before referral is considered.

If a FIT result is below the recommended threshold for referral, it is up to the clinician (in primary or secondary care) to decide on the best management, in discussion with the patient.

Updated national guidance on use of Quantitative Faecal Immunochemical Testing was published in 2025. FIT should be used as an investigation for: 

  • Repeated anorectal bleeding without an obvious anal cause 

  • Blood mixed through the stool 

  • ≥4 weeks change in bowel habit, particularly looser or more frequent stool 

  • Iron deficiency anaemia (haemoglobin below reference range and ferritin <30mg/l or confirmed on iron studies) 

  • Persistent abdominal pain (>4 weeks) and weight loss (>5%) 

FIT is not required for people with a palpable abdominal or rectal mass or unexplained anal ulceration - they should be urgently referred. Referral without FIT is possible for people who are incapable or unwilling to complete a FIT. 

Repeat FIT 

If a qFIT result is negative, a repeat FIT should be requested if your patient: 

  • presented with unexplained iron deficiency anaemia (test within 6 weeks) 

  • has persistent unexplained symptoms which cause clinical concern. 

Any positive FIT result (≥20µgHb/g) for someone with colorectal symptoms warrants urgent referral. 

If a patient has 2 negative FIT results, healthcare professionals can still consider referral along a non-USC pathway if clinically concerned. 

Wales updated their Lower Gastrointestinal Symptomatic Faecal Immunochemical Testing Pathway ‘FIT’- National Optimal Pathway in January 2023.

The indications for FIT are as follows:

  • FIT should be undertaken in people presenting with all signs or symptoms suspicious of colorectal cancer, except FIT is not required for patients with anal ulceration or anal/rectal mass prior to referral.
  • Patients with an abdominal mass suspicious of malignancy should have a FIT undertaken alongside investigation (e.g., CT abdomen) or suspected cancer referral.
  • Patients with a FIT below 10μg Hb/g faeces should still be considered for referral if symptoms are ongoing, or iron deficiency anaemia in those aged <50 or male or non-menstruating/post-menopausal women.

The Northern Ireland Cancer Network (NICaN) recommends that FIT is carried out where possible on all patients with new lower GI symptoms as part of initial investigation in general practice.  

According to guidance published in June 2024

  • Patients should be referred for further investigation if they have a result ≥10 µg Hb/g faeces. 

  • Ano-rectal mass/ulcer, abdominal mass, iron deficiency anaemia or microcytic anaemia warrant a red flag referral. A FIT result can follow referral for these symptoms.  

  • If there is significant clinician concern after two qFIT results <10 µg Hb/g, two months apart, a red-flag referral will be appropriate. 

We will update this webpage as and when further guidance is published.

Key considerations when using FIT for a symptomatic patient

  • FIT is an aid to decision-making. It should not be used to determine patient management in isolation. Safety netting those with a FIT result below the recommended threshold is vital. Consider referral for those who have a FIT result below the threshold but have ongoing concerning symptoms.
  • Clinical features - including the presence of anaemia and other signs/symptoms - remain key, as does clinical suspicion.
  • Local evaluations of FIT use within urgent suspected cancer referral pathways are emerging and welcomed. 
  • Check local pathways to understand whether primary or secondary care is responsible for requesting a FIT and actioning results.

Practical information and resources to support the optimal use of FIT

FIT is an important and useful decision aid, but evidence shows that FIT can miss around 5-17% of colorectal cancers at the recommended threshold [1-12]. This figure is collated from multiple studies, with different study populations and design, leading to a wide range in sensitivity data. It is vital to safety net patients who have received a FIT result below the recommended threshold for referral but have ongoing symptoms.

GPs may want to consider the following when safety netting patients in primary care:

  • Patients should be encouraged to notify primary if their symptoms persist, change, or worsen, even where they’ve had a negative FIT result and have been discharged.
  • Patients should not be left on patient tracking lists indefinitely, and there should be robust monitoring of numbers of patients categorised at different levels of priority and swift progression to follow on testing for all those who need it.
  • It is important to be alert to the risk of cancer in patients with unresolved symptoms, even if a follow-up test in secondary care has been negative. This includes non-GI cancers.

Evidence suggests that some groups of people are less likely to accept, complete and return a FIT. These include men, those aged under 65 years, people from ethnic minority groups and those from more deprived areas [13]. Understanding these patient groups and encouraging them to complete and return their tests is key to reducing inequalities in FIT uptake.

You can take the following steps to help support and manage your patients:

  • Be aware of key barriers to completing a FIT kit. In CRUK’s Public Omnibus survey (July 2022) the top two barriers that respondents cited to completing a symptomatic FIT were fear (10%) and embarrassment (9%) [14]. Understanding these barriers could help health professionals discuss the importance of performing and returning the test.
  • Provide patients with information and resources that will encourage and enable them to complete their test. In CRUK’s Public Omnibus survey (July 2022) the most popular prompts to completing a FIT centred around clear explanations of how to do the test (via a step-by-step guide, in-person explanations, and an online video) and information on why this test was important [14]. Please see the ‘Resources’ drop down below to access CRUK’s patient resources.
  • Overall, GPs should still urgently refer their patient if there is a clinical suspicion of cancer, despite somebody declining to take a FIT.
  • Access CRUK’s safety netting web content for more information on this topic. You can read CRUK’s safety netting web content here.
Symptomatic patients need to be tested as per local cancer referral guidelines regardless of their participation and results in bowel cancer screening programme. Equally, patients should be encouraged to participate in bowel screening at their normal interval when they are invited even if they have had a negative FIT symptomatic test.

 

Key differences in the use of FIT screening vs symptomatic

There are key differences in how FIT is used in bowel cancer screening and the investigation of symptomatic patients.

For further information, see our FIT pathway infographics: 

Patient facing resources

Download our patient guide on how to complete a FIT symptomatic kit, which contains ideas on ways to collect a poo sample.

Click here to download a version of the guide in Welsh.  

Watch CRUK's one-minute video about the symptoms of bowel cancer here, which can be shared with patients.

FIT symptomatic pathways, active research areas and references

It is vital that local pathways are kept under review, and that a set review period is established. It will be important to:

  • Assess the extent to which local pathways are being implemented as advised.
  • Monitor how long each of the pathways are taking and implement plans to shorten duration where this is not satisfactory.
  • Consider what data should be collected to support pathway review and evaluation, including the adenoma and cancer yield, and staging for patients at different levels of FIT/managed at different levels of priority.
  • Ensure that there is clarity across all local services with regards to which patients are being held on which patient tracking lists and the mechanisms in place to ensure patients are followed up within an appropriate timeframe.
  • Ensure optimal safety netting practice within primary and secondary care
  • Be aware of the differences between the symptomatic and asymptomatic (screening) uses of FIT.

The impact of FIT on colonoscopy capacity

The increased use of FIT in primary care could cause the number of urgent suspected cancer referrals to drop, and thereby increase colonoscopy capacity. In turn, this could have implications for optimisation of the bowel screening programme. However, the extent to which FIT impacts demand for colonoscopy is currently unclear.

Managing risk and FIT negative patients

One area of interest is the role of FIT in risk scores for bowel cancer, such as combining FIT with patient characteristics, blood tests and/or innovative tests. Further research is required to determine whether there is a combination of tests that perform better than FIT in isolation.

Another key area of research is the optimal management of symptomatic patients with a negative FIT (eg <10 µg) where further clarity is required on the use of a repeat FIT [15].

Understanding patient barriers and inequalities

Further evidence and insights on inequalities in access and uptake to understand why certain groups engage less with FIT and colonoscopy would be beneficial to develop strategies to mitigate this.

It should be noted that some of this information has been drawn from an emerging and evolving evidence base and so may change as more evidence is gathered and published.

 

  1. Mowat C, Digby J, Strachan JA, Wilson R, Carey FA, Fraser CG, et al. Faecal haemoglobin and faecal calprotectin as indicators of bowel disease in patients presenting to primary care with bowel symptoms. Gut. 2016;65(9):1463-9.
  2. Chapman C, Bunce J, Oliver S, Ng O, Tangri A, Rogers R, et al. Service evaluation of faecal immunochemical testing and anaemia for risk stratification in the 2-week-wait pathway for colorectal cancer. BJS Open. 2019;3(3):395-402.
  3. Mowat C, Digby J, Strachan JA, McCann R, Hall C, Heather D, et al. Impact of introducing a faecal immunochemical test (FIT) for haemoglobin into primary care on the outcome of patients with new bowel symptoms: a prospective cohort study. BMJ Open Gastroenterol. 2019;6(1):e000293.
  4. Bailey JA, Khawaja A, Andrews H, Weller J, Chapman C, Morling JR, et al. GP access to FIT increases the proportion of colorectal cancers detected on urgent pathways in symptomatic patients in Nottingham. Surgeon. 2020.
  5. Farrugia A, Widlak M, Evans C, Smith SC, Arasaradnam R. Faecal immunochemical testing (FIT) in symptomatic patients: what are we missing? Frontline Gastroenterology. 2020;11(1):28-33.
  6. Laszlo, H. E., Seward, E., Ayling, R. M., Lake, J., Malhi, A., Hackshaw, A., Stephens, C., Pritchard-Jones, K., Chung, D. and Machesney, M. (2020) Quantitative faecal immunochemical test for patients with ‘high risk’ bowel symptoms: a prospective cohort study. medRxiv, pp. 2020.05.10.20096941.
  7. Nicholson BD, James T, East JE, Grimshaw D, Paddon M, Justice S, et al. Experience of adopting faecal immunochemical testing to meet the NICE colorectal cancer referral criteria for low-risk symptomatic primary care patients in Oxfordshire, UK. Frontline Gastroenterology. 2019;10(4):347-55.
  8. Nicholson, BD, James, T, Paddon, M, et al. Faecal immunochemical testing for adults with symptoms of colorectal cancer attending English primary care: a retrospective cohort study of 14 487 consecutive test requests. Aliment Pharmacol Ther. 2020; 00: 1– 11. https://doi.org/10.1111/apt.15969
  9. D'Souza N, Georgiou Delisle T, Chen M, et al Faecal immunochemical test is superior to symptoms in predicting pathology in patients with suspected colorectal cancer symptoms referred on a 2WW pathway: a diagnostic accuracy study Gut Published Online First: 21 October 2020. doi: 10.1136/gutjnl-2020-321956
  10. N D’Souza, T Georgiou Delisle, M Chen, S C Benton, M Abulafi, O Warren, S Ahmadi, C Parchment, A Shanmuganandan, N West, T Mitchell, S Sah, N Jackson, A Myers, P Ziprin, I Bloom, S Kaye, A Ramwell, J T Jenkins, K Monahan, on behalf of the NICE FIT Steering Committee, Faecal immunochemical testing in symptomatic patients to prioritize investigation: diagnostic accuracy from NICE FIT Study, British Journal of Surgery, 2021;, znaa132, https://doi.org/10.1093/bjs/znaa132
  11. Bailey, S.E.R., Abel, G.A., Atkins, A. et al. 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. Br J Cancer 124, 1231–1236 (2021). https://doi.org/10.1038/s41416-020-01221-9
  12. Turvill, J., Turnock, D., Cottingham, D., Haritakis, M., Jeffery, L., Girdwood, A., Hearfield, T., Mitchell, A. and Keding, A. (2021) The Fast Track FIT study: diagnostic accuracy of faecal immunochemical test for haemoglobin in patients with suspected colorectal cancer. British Journal of General Practice, pp. BJGP.2020.1098.
  13. Bailey, J.A., Morton, A.J., Jones, J., Chapman, C.J., Oliver, S., Morling, J.R., Patel, H., Banerjea, A. and Humes, D.J. (2023). Sociodemographic Variations in the Uptake of Faecal Immunochemical Tests in Primary Care. British Journal of General Practice. [online] doi:https://doi.org/10.3399/BJGP.2023.0033.
  14. All figures, unless otherwise stated, are from YouGov Plc. Total sample size was 2,119 adults. Fieldwork was undertaken between 11 - 12 July 2022. The survey was carried out online. The figures have been weighted and are representative of all UK adults (aged 18+).
  15. Farkas, N., Fraser, C.G., Maclean, W., Jourdan, I., Rockall, T. and Benton, S.C. (2022). Replicate and Repeat FIT in Symptomatic Patients: A Systematic Review. Annals of Clinical Biochemistry: International Journal of Laboratory Medicine. doi:https://doi.org/10.1177/00045632221096036.