Positive Bowel Screening Test

The faecal immunochemical test (FIT) detects very small amounts of blood in the stool that are not visible to the eye. A positive result means blood has been detected. It does not specify where the blood has come from, and it does not diagnose cancer.

Bleeding may originate from polyps, haemorrhoids, a small tear in the back passage (anal fissure), inflammation in the bowel or, less commonly, from a bowel cancer. Colonoscopy is generally used to identify the source, because it examines the bowel lining directly.

The bowel screening test detects small amounts of blood in the stool. It does not remove polyps. If a subsequent colonoscopy identifies polyps, they can often be removed during the procedure. Whether colonoscopy is appropriate, and when, depends on your findings, medical history and your treating team.

Colonoscopy allows direct examination of the large bowel lining and, where appropriate, treatment of polyps in the same procedure. It is the investigation most commonly recommended after a positive FIT because it can both identify the source of bleeding and address polyps that are found.

Even when no cancer is identified, colonoscopy is rarely wasted. Removing polyps that are found can reduce future bowel cancer risk, and identifying common conditions such as haemorrhoids or diverticular disease allows symptoms to be managed appropriately.

Most people will be referred for colonoscopy, which should be arranged without unnecessary delay. Your GP or specialist will advise the appropriate timing for you.

Repeating the FIT test after a positive result is not generally recommended, as a subsequent negative test does not exclude a significant cause.

If you have received a positive FIT result, make an appointment with your GP. Your GP will review your medical history, examine you, and where appropriate provide a referral for colonoscopy.

• See your GP to discuss the result.
• Bring the screening program letter to the appointment.
• Tell the GP about any symptoms, medications and family history of bowel cancer.
• Follow the advice of your GP and specialist on the appropriate next step and timing.

If colonoscopy is booked, you will receive written bowel preparation instructions from the practice or hospital. Follow only the instructions provided by your treating team for your procedure. General information on this website is not a substitute for those instructions.

Some medicines may need individual advice before the procedure. Do not stop, change or delay any regular medicine unless you have received specific instructions from your treating team.

Colonoscopy is performed as a day procedure under sedation given by a specialist anaesthetist. The examination commonly takes approximately 20 to 40 minutes, although this varies according to what is required. Most patients have no recollection of the procedure and minimal discomfort afterwards.

Any polyps identified may be removed during the same procedure, and small tissue samples may be taken for pathology. Visible findings are discussed in recovery, and biopsy results are reviewed at follow-up, usually within one week.

If no polyps or other growths are found, the National Bowel Cancer Screening Program will usually invite you to screen again four years after the colonoscopy. Your specialist and GP will confirm the appropriate timing for you.

If polyps are removed, your specialist will confirm the timing of any further colonoscopy once the pathology results are available. If bowel cancer is identified, you will be guided through the next steps, which may include staging scans and discussion of treatment options.