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This publication is available at https://www.gov.uk/government/publications/bowel-cancer-screening-benefits-and-risks/nhs-bowel-cancer-screening-helping-you-decide
Public Health England (PHE) created this information on behalf of the NHS. In this information, the word ‘we’ refers to the NHS service that provides screening.
It’s your choice whether to take part in bowel cancer screening. This leaflet aims to help you decide.
Why we offer bowel cancer screening
We offer screening to detect bowel cancer when it is at an early stage in people with no symptoms. This is when treatment is more likely to be effective. Screening can also find polyps. These are abnormal clumps of cells in the bowel. Polyps are not cancers, but may develop into cancers over time. Polyps can be easily removed, which reduces the risk of bowel cancer developing.
Regular bowel cancer screening reduces the risk of dying from bowel cancer.
Who we invite
We offer bowel cancer screening using a home testing kit to everyone in England from the age of 60. Your GP practice gives us your contact details so please make sure they always have your correct name, date of birth and address. Many GPs also like to have your mobile number and email address.
We offer screening every 2 years between the ages of 60 and 74. We are gradually extending this age range, and people aged 56 are now being invited as part of this process. If you are over 74, you can ask for a kit every 2 years by calling our free helpline on 0800 707 60 60.
You may be asked to take part in a research project (a ‘clinical trial’). Research helps the NHS improve bowel cancer prevention and treatment for people in the future. You can choose whether to take part or not. Your choice will not affect your bowel cancer screening.
How the bowel works
The bowel is part of your digestive system. It takes nutrients and water from food and turns what is left into poo (also known as faeces, stools or bowel motions). As illustrated below, the colon and rectum make up the large bowel.
Bowel cancer is also known as colon, rectal or colorectal cancer. Sometimes the cells that make up the bowel grow too quickly and form a clump of cells known as a bowel polyp (some types of polyp are called an ‘adenoma’). Polyps are not bowel cancers but they can sometimes change into a cancer over a number of years.
Risks of developing bowel cancer
Everyone, whatever your sex, is at risk of developing bowel cancer. Things that can increase your risk include:
- getting older (8 out of 10 people diagnosed with bowel cancer are over 60)
- not being active enough
- being overweight
- a diet high in red and processed meat and low in fibre, vegetables and fruits
- drinking too much alcohol
- having type 2 diabetes
- having inflammatory bowel disease (ulcerative colitis or Crohn’s disease)
- a family history of bowel cancer
How bowel cancer screening works
We send you an invitation letter with information about bowel cancer screening. The information is to help you decide whether to take part. Then we send you a faecal immunochemical test, or ‘FIT kit’ for short. It detects blood in your poo (blood you would not notice by eye). We look for blood because polyps and bowel cancers sometimes bleed. Finding blood does not diagnose bowel cancer but it means you need further tests (usually a bowel examination).
Most people’s screening result shows they do not need any further tests.
Some people will need further tests. If this is the case for you, we will offer you an appointment to talk about having a colonoscopy. Colonoscopy looks at the inside of your bowel. We use colonoscopy to find the source of the blood.
Reduce your risk of bowel cancer
Having bowel cancer screening reduces your risk of dying from bowel cancer by at least 25% [footnote 1].
You can also reduce your risk of bowel cancer by:
- keeping physically active
- keeping a healthy weight
- eating plenty of fibre – for example, choose wholegrain and wholemeal foods
- eating plenty of vegetables and fruit
- eating less red meat and especially less processed meat
- drinking less alcohol
- not smoking
Using the FIT kit
The animation is available with subtitles and in British Sign Language. Subtitled versions are provided in English, Arabic, Bengali, Chinese (simplified and traditional), Farsi, Gujarati, Polish, Portuguese, Punjabi and Urdu.
You use the FIT kit in the privacy of your home. It’s a simple way to collect a tiny sample of poo. The kit (pictured below) is a small plastic bottle with a stick attached inside the lid. You use the stick to collect the sample, which you seal into the bottle. There are instructions with each kit.
Once used, you post the kit in its prepaid packaging to a laboratory for processing. Using the kit takes just a few minutes and it’s an easy and effective way to screen for early bowel cancer.
If you’re not sure whether you should use the kit, please call our free helpline on 0800 707 60 60 for advice. For example, if you have had surgery and have an artificial opening that allows poo from the bowel to pass (a stoma) then you might want to call us.
Bowel cancer screening results
You should receive a results letter within 2 weeks of sending in your sample. As shown in the flowchart above, there are 2 possible results.
No further tests needed at this time
Most people (about 98 out of 100) have this result. It means that we did not find any blood in your sample, or only a tiny amount which is within the screening range.
This result does not guarantee that you do not have bowel cancer, or that it will never develop in the future. Being aware of the symptoms of bowel cancer is very important. We will offer you bowel cancer screening again in 2 years’ time if you are under the age of 75.
Further tests needed
About 2 in every 100 people have this result. It means that we found an amount of blood in your sample above the screening range.
This does not mean that you have cancer, but it does mean we will offer you an appointment to discuss having a colonoscopy. Several things can cause blood in poo, such as:
- haemorrhoids (piles)
- bowel polyps
- bowel cancer
Having further tests (usually a colonoscopy) means we can look for the cause of the blood.
What happens to samples after testing
Once we have analysed the FIT sample, we record the result onto a database and then destroy the test kit and contents.
We keep the database information so we can check you are treated correctly. We also use it to monitor the performance of the bowel cancer screening programme.
If you need further tests
We will offer you an appointment at a local screening centre (usually in a hospital). This is to discuss having a more detailed examination of your bowel (colonoscopy). The colonoscopy is to see if there is a problem that needs treatment.
A specialist screening practitioner (SSP) will talk with you about your screening result and answer any questions you have. He or she will discuss colonoscopy with you, and check if you are fit enough for the procedure.
If you are fit for colonoscopy and want to go ahead with the examination, we will arrange an appointment for you. If we do not think you are fit enough for colonoscopy, we may offer you a different investigation such as a computerised tomography (CT) scan (sometimes called a ‘virtual colonoscopy’).
Only around 2 in 100 people who complete the FIT kit need a colonoscopy.
Colonoscopy looks at the lining of your large bowel. A colonoscopy specialist (usually a doctor or nurse) passes a thin flexible tube with a tiny camera attached (a colonoscope) into your back passage (rectum). They guide the colonoscope around your large bowel. If they find any polyps, they can usually remove them painlessly using a wire loop passed down the colonoscopy tube. They will check any removed polyps for cancer cells.
Colonoscopy is the best way to diagnose bowel cancer. For most people, colonoscopy is straightforward. But as with most medical procedures, complications can happen. These include:
- a hole (perforation) in the bowel caused by the colonoscope (around 1 person in 1,700); around half of people with a perforation will need surgery to repair it
- heavy bleeding needing a transfusion (around 1 person in 2,400)
In rare cases, colonoscopy complications may result in death. However, in a national audit of 20,086 colonoscopies carried out in 2011, no deaths were recorded[footnote 2].
For more information, you can read our leaflet about colonoscopy.
Remember, most people who complete the FIT kit will not need a colonoscopy
Possible benefits and risks of bowel cancer screening
Being aware of the possible benefits and risks will help you decide whether or not to take part in bowel cancer screening.
Bowel cancer screening:
- reduces your risk of dying from bowel cancer by at least 25%
- allows us to remove any polyps found during colonoscopy, which reduces your risk of developing bowel cancer
- can be completed at home in private
Bowel cancer screening might:
- cause complications, for example, during or after colonoscopy
- miss a cancer if it was not bleeding when you used the FIT kit
It is important to be aware of the symptoms of bowel cancer even if you have screening. No screening test is 100% effective. If you do not need further tests after using the FIT kit this does not guarantee that you do not have bowel cancer, or that it will never develop in the future.
No screening test is completely effective. In bowel cancer screening this is because:
- a polyp or cancer can sometimes be missed if it was not bleeding when the screening test was taken (a ‘false negative’ result)
- bowel cancer may develop in between screening tests
Bowel cancer symptoms
Symptoms of bowel cancer include:
- blood in your poo (faeces)
- looser poo, pooing more often and/or constipation
- a pain or lump in your abdomen (tummy)
- feeling more tired than usual for some time
- losing weight for no obvious reason
Please remember that these symptoms do not necessarily mean that you have bowel cancer. But if you have any of these symptoms for 3 weeks or more, please speak with your GP. It is important to do this even if you have recently had bowel cancer screening or a colonoscopy.
Bowel cancer screening is not a test for symptoms.
Treatment for bowel cancer
A diagnosis of bowel cancer is unlikely. But if it does happen, we will refer you to a team of specialists who will look after you.
If the cancer is in a polyp removed during a colonoscopy, regular check-ups may be all you need.
The main treatment for bowel cancer is surgery. In some cases, the specialists may offer you chemotherapy or radiotherapy.
Not all bowel cancers found at screening are curable. But for people who have bowel cancer found at its earliest stage, over 90% are still alive 5 years later. [footnote 3]
The NHS screening programmes use personal information from your NHS records to invite you for screening at the right time. Public Health England also uses your information to ensure you receive high quality care and to improve the screening programmes. Find out more about how your information is used and protected, and your options.
For more information about bowel cancer screening call our free helpline on 0800 707 60 60.
If you have hearing or speech difficulties you can use the Relay UK service to contact us. Dial 18001 then 0800 707 60 60 from your textphone or the Relay UK app.
You can also:
- talk to your GP
- read the NHS.UK information on bowel cancer screening
- visit GOV.UK and search for ‘bowel cancer screening’
- read our leaflet about colonoscopy
- read information for transgender and non-binary people about NHS population screening programmes
If you are 75 or over and would like a FIT kit, please call our free helpline on 0800 707 60 60. You can ask for a kit every 2 years.
Find out how to opt out of screening.
Except where indicated, all statistics are from PHE.
Hewitson P and others. ‘Cochrane systematic review of colorectal cancer screening using the fecal occult blood test (hemoccult): an update’. American Journal of Gastroenterology 2018: 103(6), pages 1541 to 1549. ↩
Gavin, DR and others. ‘The National colonoscopy audit: a nationwide assessment of the quality and safety of colonoscopy in the UK’. Gut 2013: 62(2), pages 242 to 249. ↩