Patient information · Screening
Bowel screening and the FIT test
what a result does and does not tell you
Bowel cancer is one of the most treatable cancers when found early and one of the least when found late, and it often causes no symptoms at all until it is advanced. Screening exists to catch it in that silent window. The test is quick, done at home, and around a third of people who are sent one never return it.
Do not wait for screening if you have
- blood in your stool, or bleeding from the back passage
- a persistent change in bowel habit lasting three weeks or more
- unexplained weight loss, or persistent abdominal pain
- a lump in the abdomen, or a feeling of incomplete emptying
- unexplained iron deficiency anaemia
Screening is for people without symptoms. A negative FIT result does not exclude cancer in someone who has symptoms — it means no blood was detected in that particular sample on that particular day. Symptoms need investigating on their own merits.
Who is invited
The programme was extended down to age 50 in stages, so if you are in your early fifties and have not yet had a kit, you may simply not have reached your invitation point. You can check with the screening helpline.
What the test measures
FIT detects tiny amounts of human blood in a stool sample — quantities invisible to the eye. Bowel cancers and larger polyps tend to bleed intermittently, so blood can be present long before anything is noticeable. It requires a single small sample, takes a couple of minutes, and no dietary preparation.
- The sample is taken with a small stick built into the tube. Instructions are in the pack.
- Post it back promptly — samples degrade if left around, and delayed kits are a common cause of an inadequate result.
- If you are having a period or have visible piles bleeding heavily, wait until that has settled.
Understanding the result
- No further tests needed — the great majority. You will be invited again in two years. This does not mean you can ignore symptoms in the meantime.
- Further tests needed — blood was detected. This is not a cancer diagnosis. Most people with a positive FIT do not have cancer; the commonest findings are polyps, piles, diverticular disease or inflammation. You will be offered a colonoscopy.
- Unclear or spoilt sample — you will be sent another kit. Common and not concerning.
Polyps are the point of screening
Most bowel cancers develop over 10 to 15 years from a polyp — a small growth on the bowel lining. Colonoscopy allows polyps to be removed during the same procedure, which prevents the cancer from ever forming. Screening therefore does more than find cancer early; it stops a proportion of cancers happening at all.
Colonoscopy
A flexible camera examines the whole large bowel, usually with sedation. The preparation — strong laxatives the day before — is the part most people find difficult, and following it properly matters, because a poorly prepared bowel means a poor view and often a repeat. Alternatives such as CT colonography exist where colonoscopy is unsuitable.
Reducing your risk
- Reduce red and processed meat; increase fibre, fruit, vegetables and wholegrains.
- Keep alcohol low and stop smoking.
- Stay physically active and maintain a healthy weight.
- Know your family history — a parent, sibling or child diagnosed under 50, or several affected relatives, may mean you need earlier and more frequent surveillance rather than routine screening.
Book an appointment if you have symptoms, you have a family history you would like assessed, you are under 50 and concerned, or you would like a FIT test or colonoscopy without waiting for a screening invitation. We offer FIT testing and blood tests on site, and arrange colonoscopy through our CQC-registered partners.
FIT testing on site, colonoscopy without the wait
Seven days a week, 9am–7pm, on Whitechapel Road.
Tower Bridge Hospital London
97–99 Whitechapel Road, London E1 1DT
WhatsApp 07903 284 189
info@mhwclinic.co.uk
Open Mon–Sat, 9am–7pm (closed Sundays until September)
In an emergency
Call 999, or go to the Royal London Hospital Emergency Department, Whitechapel Road, London E1 1FR.
When we are closed and it is not an emergency
Call NHS 111 or visit 111.nhs.uk.