Positive FIT Test: What Does It Mean and What Happens Next?

A FIT test, or faecal immunochemical test, is a stool test that checks for tiny amounts of blood in your poo. It is used in the NHS bowel cancer screening programme and is also used by GPs when patients have bowel symptoms that need further assessment.

A positive FIT test means that blood has been detected in your stool sample. It does not tell us where the blood has come from and it does not diagnose cancer. It means the result needs to be interpreted alongside your symptoms, age, medical history and risk factors.

In many cases, the next step is a specialist assessment and often a colonoscopy to look directly inside the bowel.

No. Most people with a positive FIT test will not have bowel cancer. However, because bowel cancer and bowel polyps can bleed intermittently, a positive FIT test should not be ignored. The purpose of further investigation is to identify the cause of the bleeding and, importantly, to rule out serious disease.

A positive FIT test can be caused by several bowel conditions, including:

– Haemorrhoids or piles
– Anal fissures
– Bowel polyps
– Diverticular disease
– Inflammatory bowel disease
– Infection or inflammation
– Bowel cancer

Even if you have known haemorrhoids, it is important not to automatically assume they are the cause of a positive FIT test.

The usual next step is to discuss the result with a clinician. They will review your symptoms, medications, previous colonoscopy history, family history and general health. Depending on the situation, you may be advised to have a colonoscopy, which is a camera test that examines the inside of the large bowel.

A colonoscopy is a test where a thin flexible camera is passed through the back passage to examine the rectum and colon. It allows the specialist to look for inflammation, polyps, diverticular disease, cancer or other causes of bleeding. If polyps are found, they can often be removed during the same procedure and sent for laboratory analysis.

Not always, but it is commonly recommended, especially if the FIT level is clearly positive or if you have symptoms such as rectal bleeding, change in bowel habit, unexplained anaemia, abdominal pain or weight loss. The decision depends on your full clinical picture.

A screening FIT is sent to people in the NHS bowel cancer screening programme, usually when they feel well and have no symptoms. In England, bowel cancer screening is offered to people aged 50 to 74 every 2 years.

A symptomatic FIT is requested when someone has symptoms that may need investigation. In symptomatic patients, NICE recommends urgent colorectal cancer pathway referral when FIT is at least 10 micrograms of haemoglobin per gram of faeces, but referral should not be delayed if there is clinical concern. 

The FIT number reflects the amount of blood detected in the stool sample. A higher number generally means more blood was detected. However, the meaning of the number depends on whether the test was done as part of screening or because of symptoms.

For patients with symptoms, even relatively low positive FIT levels may need further assessment. The number should always be interpreted alongside your symptoms and clinical history.

Usually, if a FIT test is positive, the priority is to understand why it is positive rather than simply repeating the test. Bleeding from bowel conditions can be intermittent, so a later negative result does not always remove the need for assessment if symptoms or risk factors are present.

Yes, although the risk is lower. A negative FIT test is reassuring, but it does not completely rule out bowel cancer. NICE specifically states that referral should not be delayed if there is clinical concern, even in the absence of a FIT result.

You should seek medical advice if you have:

– Blood in your poo or bleeding from the back passage 
– A persistent change in bowel habit 
– Looser stools, diarrhoea or constipation that is unusual for you 
– Unexplained weight loss 
– Abdominal pain or bloating 
– A lump in the abdomen 
– Unexplained tiredness or iron-deficiency anaemia

These symptoms do not always mean cancer, but they should be properly assessed.

Yes, haemorrhoids can bleed and may contribute to a positive FIT test. However, haemorrhoids are common, and their presence does not automatically explain a positive result. If the FIT test is positive, particularly with other bowel symptoms, further assessment may still be needed.

Yes. Some bowel polyps can bleed. Polyps are important because some types can develop into cancer over time. During colonoscopy, many polyps can be removed before they cause future problems.

If a polyp is found during colonoscopy, it can often be removed at the same time. It is then sent to the laboratory to determine the type of polyp and whether any further treatment or surveillance colonoscopy is needed.

If bowel cancer is found, the next step is usually staging with scans and discussion in a specialist multidisciplinary team meeting. Treatment may involve surgery, chemotherapy, radiotherapy, immunotherapy or a combination, depending on the exact type, position and stage of the cancer.

Yes. Many patients choose to arrange private assessment because they want quicker answers, continuity with a named consultant, or more control over appointment timing. You should bring your FIT result, GP referral information, medication list and any previous colonoscopy reports to your consultation.

Yes. Your GP should remain aware of your FIT result and any private investigations, especially if you were referred through an NHS pathway or have ongoing symptoms. Private and NHS care should be properly joined up so that results are not missed.

Many private medical insurance policies cover specialist consultation and colonoscopy if there is a clinical indication. You should contact your insurer before your appointment to confirm authorisation, excess payments and whether a GP referral is required.

Yes. Self-pay patients can arrange a private consultation and, if needed, receive a quote for colonoscopy or further investigation. Fees vary depending on the hospital, anaesthetic/sedation requirements, pathology and whether any polyps are removed.

A positive FIT test should be taken seriously and assessed promptly, especially if you have symptoms such as rectal bleeding, change in bowel habit, anaemia, weight loss or abdominal pain. If you are concerned, arranging a consultation can help clarify the next step and avoid unnecessary delay.

Please bring:

– Your FIT result, including the numerical value if available
– A list of your symptoms and when they started
– A list of medications, especially blood thinners
– Details of previous colonoscopies or bowel investigations
– Any family history of bowel cancer or polyps
– Your insurance authorisation number, if insured

Many patients feel embarrassed about bowel symptoms, bleeding or haemorrhoids. These problems are extremely common and are assessed in a professional, discreet and respectful way. The aim is to give you a clear diagnosis and a plan.