Screening
Bowel Cancer Screening (FIT)
Bowel cancer screening uses a simple home test (FIT) that checks a stool sample for hidden blood, which can be an early sign of bowel cancer or polyps.
Quick answer
Bowel Cancer Screening (FIT): what it is and what the results mean
The faecal immunochemical test (FIT) detects tiny amounts of blood in the stool that cannot be seen. A small home kit is used to collect a sample, which is sent to a laboratory for testing.
- Why it is done: It is offered routinely by age to find bowel cancer early, often before symptoms, and to detect polyps that could become cancer.
- Understanding results: A normal result means no significant blood was found and you are recalled at the next interval.
What it is
The faecal immunochemical test (FIT) detects tiny amounts of blood in the stool that cannot be seen. A small home kit is used to collect a sample, which is sent to a laboratory for testing.
Why it is done
It is offered routinely by age to find bowel cancer early, often before symptoms, and to detect polyps that could become cancer. Finding it early makes treatment much more likely to succeed.
What to expect
You collect a small sample of your stool at home using the kit provided and post it back. It is quick, private and does not require any diet change for the standard test.
Understanding the results
A normal result means no significant blood was found and you are recalled at the next interval. If blood is found, you are usually offered a colonoscopy to look inside the bowel, as blood can have many causes besides cancer.
Good to know
Risks and limitations
The home test itself is completely safe. It can occasionally miss a problem or flag one that turns out to be harmless, which is why it is repeated at intervals and followed up with a colonoscopy when positive.
Education and reference only. This explains the test in general terms and is not medical advice. Always follow the specific instructions from the team arranging your test, and discuss your results with your clinician.
Answers
Bowel Cancer Screening (FIT): frequently asked questions
What does a positive FIT result mean?
It means blood was detected in your stool sample. This can be due to many things, not just cancer, so you will usually be offered a colonoscopy to look inside the bowel and find the cause.
Do I need to change my diet before a FIT test?
No. Unlike older tests, the FIT test does not usually require any change to your diet. Simply follow the instructions in the kit to collect and return your sample.
Related tests
Other screening investigations
Sources
Where this is drawn from
- NHS — Tests and treatments
- NICE — diagnostic guidance
- UK National Screening Committee / relevant professional body
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