Bowel Screening
What is the NHS bowel cancer screening programme?
Bowel cancer is a general term for cancer that begins in the large bowel. Depending on where the cancer starts, bowel cancer is sometimes called colon cancer, rectal cancer or colorectal cancer. Bowel cancer screening aims to detect bowel cancer at an early stage, in people with no symptoms. This is when treatment is most likely to be effective. Bowel cancer screening can also detect polyps in the bowel. These are not cancers, but may develop into cancers over time. Polyps can be easily removed, reducing a person's future risk of bowel cancer.
Screening for bowel cancer in the UK involves three stages, firstly identifying the people in the population who are most at risk, secondly offering people in that age group a screening test (the Faecal Occult Blood test), and thirdly offering a diagnostic test (such as a colonoscopy) to those who have had an abnormal Faecal Occult Blood test result.
Polyps and bowel cancers sometimes bleed which is why we screen for blood in bowel motions (stools or faeces). A man we talked to about screening pointed out that blood in a motion may be due to something else, such as piles, but that an abnormal Faecal Occult Blood test result needs further investigation.
The Faecal Occult Blood test detects hidden blood in a person's motion. Blood in the motion indicates that another test is needed, such as a colonoscopy.
The Faecal Occult Blood test detects hidden blood in a person's motion. Blood in the motion indicates that another test is needed, such as a colonoscopy.
What do you think is meant by screening, when we say screening for bowel cancer?
Basically it's to detect blood in your stool, that's the indicator which says to them it needs further investigation. If there's blood in your stool it shouldn't be there and if the reason, I mean it could be a simple reason, people have piles, it could be any reason, but if it is to do with a malignant bowel cancer then the earlier it's treated, and I believe it can be treated successfully and obviously it's to the good and you must have it done. It won't go away, it's no good burying your head in the sand, it needs to be investigated and treated and then your chances of coming out successfully obviously have got to be much better.
Many women understand what is meant by “screening” because they have mammography as part of screening for breast cancer and smear tests as part of screening for cervical cancer.
She describes screening as a form of 'sifting' to find people who may need treatment.
She describes screening as a form of 'sifting' to find people who may need treatment.
Do you think people understand what is meant by screening?
Well I think that they have, women especially, realise with the mammography, with the breast screening and also the smear test is another screening isn't it, so yes I think, I think we know what screening means, that they go through everyone to find, a sifting really of finding the good, you know the bad ones that need treatment.
So when you say they go through everyone, can you say a little bit more about that for those people who might not understand?
Well they do a test on everyone who presents themselves for testing to find any problems that may crop up, any problems even in the early stages of the problems so that they can be caught early and the operation is not as, not such a big operation is needed to clear things up.
So anybody, even people who are perfectly healthy would be invited to be screened?
I'm perfectly healthy and I, I was, yes I am perfectly healthy now, but I did have my doubts.
Some understood that the purpose of screening was to catch an illness at an early stage, before there were symptoms, but the idea of screening is not familiar to everyone. One woman said that when she first heard about the screening programme she thought of the Big Screen and wondered if she would be filmed. A man thought that the word “screening” sounded a bit technical and preferred to call it a 'check-up'.
He prefers the term check-up.
He prefers the term check-up.
When people are invited for screening for bowel cancer what do you think they think is meant by that?
I think people think there is a, there is, possibly that there is already cancer there or you know I think screening is a very, very technical term and I would think easier is to say having a check up to ensure that there isn't any problems and you know, sooner than screening, putting it in normal term, terminology, that screening perhaps is a bit too disastrous really. I think it would better if it just said check-up to ensure there isn't any bowel problems.
At first she thought that screening might involve a film.
At first she thought that screening might involve a film.
Very interesting.
Mm they might, mightn't they?
A really interesting point. And now what's your understanding of screening?
Well my understanding of it now is you just get your kit and away you go.
It is known that taking part in regular bowel cancer screening reduces the chance of dying from bowel cancer by about 16% but it is important to consider the disadvantages as well as the advantages of screening (Cochrane Database of Systematic Reviews 2006). The screening process is not completely safe, and bowel cancer may be missed during a colonoscopy.
Sir Muir Gray discusses some of the advantages and disadvantages of screening.
Sir Muir Gray discusses some of the advantages and disadvantages of screening.
All screening programmes do harm - we are very conscious of that. In fact all medical care does harm. But when you've got something wrong with you, you go and see the doctor, you accept that there's a risk of side effects. But when we send you a letter, to a healthy person like yourself, aged 65 or 62 or whatever, and we invite you as a healthy person to come and be screened, then we've got to be doubly careful about the risks. So the disadvantage of screening, that people have reported to us, firstly there is anxiety, some people don't like the thought of it, some don't like to do the test for bowel cancer screening. So there are psychological issues. These almost always go away very quickly, but we know that people get anxious. The thing that really worried us about bowel cancer screening was the fact that in the tests, the colonoscopy, it is like any intervention in medicine, it carries a risk, and for this reason, we've designed a bowel cancer screening programme like a Japanese car industry. We've paid attention to quality and safety at every stage in the process. So there are disadvantages. It's not perfect. Some people with bowel cancer will not be detected as a result of the screening programme. Some of the people we've found with bowel cancer, even if they are having treatment, it may not help them have a better outcome. The advantages of bowel cancer screening are that if you are of the age which we invite you to come for a screening, it is the single best means of reducing your risk of dying of bowel cancer. So, we are very careful to say to people, 'We are making an invitation to you, we are offering you the opportunity to be involved. There are disadvantages, we have taken great care to try to minimise those disadvantages, and maximise the advantages, but it is really up to you to decide what you want to do.'
In England, Wales and Northern Ireland the NHS Bowel Cancer Screening Programme offers screening every two years to all men and women aged 60-74. The national bowel screening programme in Scotland screens men and women aged between 50 and 74 years (Scottish Bowel Screening Programme). People did not always understand that everyone in the age group was invited to take part - some thought their name had been drawn at random, or for some other purpose (See 'Initial reaction to the invitation for screening'). Some people wondered why screening is offered only to people in that age group.
Sir Muir Gray explains why people aged between 60 and 69 are offered screening for bowel cancer.
Sir Muir Gray explains why people aged between 60 and 69 are offered screening for bowel cancer.
Well somebody said to me once that the first screening test is looking at your birth date. And when we take a screening programme we look at a subset of the whole population so we don't see any point in offering people of 30, bowel cancer screening. Some people do get bowel cancer at age of 30, but it is very, very uncommon. So what we try to do is identify the population in which the benefits are greatest because then the balance of benefits to risks is most favourable. So we did modelling, we looked at different options for screening and came to the conclusion that people in their 60's were those who stood most to benefit, and for this reason the first screening test we do is to identify people through your medical records to make you the offer of attending for screening.
For more information about the NHS Cancer Screening Programme for bowel cancer phone 0800 707 6060 and ask for a leaflet (see resources) or visit their website for a copy.
Flexible sigmoidoscopy (flexi-sig) screening
The NHS has also decided to introduce bowel scope screening (flexible sigmoidoscopy (flexi-sig) screening) for all men and women when they reach the age of 55. The pilot began in March 2013 with men and women in six pilot areas being invited for 'bowel scope screening' around the time of their 55th birthday. This new test is not yet available everywhere across England. The target is for all screening centres to offer bowel scope screening by December 2016. Flexible sigmoidoscopy is a way of looking at the inside of the bowel using an endoscope (a thin flexible tube that is put into the rectum/back passage and guided around the lower part of the bowel) to detect bowel polyps and cancers early before any symptoms develop.
Last reviewed May 2016.
Last updated May 2016.
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