Bowel cancer: should I be screened?

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1 Patient information from the BMJ Group Bowel cancer: should I be screened? Bowel cancer is a serious condition, but there are good treatments. Treatment works best if it's started early.to pick up early warning signs of cancer, you might wish to consider a screening test. What is bowel cancer? Bowel cancer is one of the main causes of death from cancer in the UK. The cancer starts when some cells in the inside wall of the bowel start dividing too fast.you can get treatment to try to remove or kill the cancer and stop it spreading to other parts of your body. The term 'bowel cancer' includes cancers of the colon and rectum, which make up the upper and lower part of your bowel. Bowel cancer is sometimes called colorectal cancer. Your bowel turns food your body doesn't need into solid waste. The waste then leaves your body when you go to the toilet. What is bowel cancer screening? Cancer screening means looking for signs of cancer in healthy people. The idea is to spot cancer early, so treatment can be started straight away. There are several different tests that can spot early signs of bowel cancer. The one used most often in the UK is the faecal occult blood test (FOBT for short). If you have this test, a sample of your stool (faeces) is tested for blood. If you have blood in your stools, it might be because you have a tumour in your bowel. Older people in the UK will be offered this test every two years.the screening programme will be carried out by post.you do the test at home, using a kit.you place a small amount of your stool onto test cards. Then you return the cards to the screening centre so they can be checked for traces of blood. If the test finds blood, it doesn't mean you have cancer. Most people who have a positive test don't actually have cancer. The test means you might have cancer, and you should have another test to find out. Should I be screened? Regular screening for bowel cancer is now recommended in most of the UK for men and women over 60. People who are at high risk of bowel cancer can get tested earlier and more often. In England, people aged 60 to 69 years are offered FOBT screening every two years, using a home test. This age range is gradually being extended to include people up to page 1 of 5

2 age 75. If you're over 70 and you want to be screened, you can ask to be sent a testing kit. A similar programme has also started in Northern Ireland. In Scotland, men and women aged 50 to 74 are offered FOBT screening every two years. In Wales, those aged 60 to 74 are offered this screening, although the programme hopes to start screening from age 50 in the next few years. If you are not covered by these screening programmes, you could choose to pay for screening at a private health clinic. But it is a good idea to check out the clinic with your GP first. These screening programmes are for men and women who have an average risk of getting bowel cancer. This means they have no health problems or family history that puts them at higher risk of bowel cancer. In England, a test to examine the rectum and lower bowel is gradually being added to the screening programme. This one-off test, called a flexible sigmoidoscopy or bowel scope, will eventually be offered to all men and women aged 55. FOBT screening will continue to be offered as before. How can screening help? Screening is used to look for cancer at a very early stage, before it starts to cause symptoms. The earlier bowel cancer is found, the more likely it is to be cured. Studies show that: If your bowel cancer is found after it has started causing symptoms, you have a 5 in 10 chance of surviving for at least five years If your bowel cancer is found before it has started causing symptoms, you have an 8 in 10 chance of surviving for at least five years. There is good research to show that the faecal occult blood test works well for bowel cancer screening. People who have this test once a year or once every two years, with a follow-up colonoscopy if the results are positive, are less likely to die of bowel cancer. In one study of 46,000 people, there were about one-third fewer deaths from bowel cancer in people who had FOBT screening every year for 13 years, compared with people who had no screening. But FOBT doesn't pick up every case of bowel cancer. Can it be harmful? Most people being screened don't have cancer. So it's important that the benefits of having a screening test outweigh the risk of any harm. That's why it's important to know which tests are safest for screening. FOBT is a safe test.you don't have to undergo any procedure. But there are two possible problems: page 2 of 5

3 False-negative results. This means you do have cancer, but the test doesn't find it. So you might ignore symptoms of cancer and miss out on vital treatment. FOBT doesn't pick up every case of bowel cancer, because not all cancers bleed False-positive results. This means you don't have cancer, but the test result is positive. So you get needlessly worried and have more tests that you don't really need. Most people who have a positive FOBT do not have cancer. This is because there are lots of other medical problems that cause bleeding from the back passage. What will happen after my test? If you have a negative result A negative result means the test did not find any signs of cancer. This is reassuring. But remember that the FOBT sometimes misses cases of cancer. Even if you've had a negative test result, you shouldn't ignore warning signs of bowel cancer. You should see your doctor if you have any of these symptoms, which could mean bowel cancer: Repeated bleeding from your back passage Seeing blood in your stools A change in your bowel habits that lasts for more than six weeks. This could be loose stools and needing to go to the toilet more often, or bad constipation Bad pain in your abdomen Unexplained weight loss or severe tiredness. If you have a positive result A positive FOBT result may make you feel very anxious. But a positive test doesn't mean you have cancer. You will need another test to find out. Other tests There are several other types of test for bowel cancer but they aren't used routinely for screening in the UK. That's because they involve doctors putting a tube into your back passage. This can be uncomfortable and there's a risk that the tube will damage the bowel. However, these tests are very thorough. In the UK, they are normally used to test for bowel cancer when someone has symptoms of bowel cancer, or is at high risk of bowel cancer, or has a positive FOBT test. page 3 of 5

4 If you have flexible sigmoidoscopy, a doctor puts a thin, bendy tube into your back passage. This allows the doctor to look at your rectum and the lower part of your bowel. If you have colonoscopy, a doctor puts a tube into your back passage.this is pushed up your bowel so the doctor can see all the way along it. If you have a barium enema, a thick white liquid is put into your rectum through a tube in your back passage. Then x-rays are taken of your bowel. These tests also allow the doctor to see if you have polyps.these are growths or patches of cells in the bowel wall. If you have polyps you might need to have them removed. Polyps are not the same as cancer. But most cancers start as polyps. If you have flexible sigmoidoscopy or colonoscopy, there's a small chance the instruments used to carry out the test could damage your bowel. This could cause bleeding bad enough to go to hospital. In one study of more than 40,000 people having flexible sigmoidoscopy, three people had to go to hospital with bleeding. There's a slightly bigger chance that colonoscopy could damage your bowel. In another study, six out of more than 3,000 people having colonoscopy had serious bleeding. If you've had a positive result from FOBT or any other type of test, you will probably have a colonoscopy. Colonoscopy is a very thorough test for bowel cancer, because it can see the full length of the bowel. If the colonoscopy finds any polyps, these can be removed during the test. Having polyps doesn't mean you have cancer now, or that you will get it later. But bowel cancer usually starts with polyps. So you should be tested more regularly from now on. If the colonoscopy test finds any abnormal-looking areas in the bowel, the doctor will remove a small piece of tissue during the test. Doctors call this taking a biopsy. This tissue is then sent to a laboratory, where it is examined under a microscope. If there are cancer cells in the sample, you will be referred to a doctor who specialises in bowel cancer. The doctor will need to do some further tests to find out how big the cancer is and whether it has spread. This helps the doctor plan the best treatment for you. The main treatments for bowel cancer are surgery, radiotherapy, and chemotherapy (treatment with anti-cancer drugs). People at high risk of bowel cancer Things that increase your risk of getting a disease are called risk factors. If you have a condition or family history that puts you at high risk of bowel cancer you might need regular tests (flexible sigmoidoscopy, colonoscopy, or barium enema). Your doctor will be able to advise you.you should have a special screening plan if you have any of these risk factors for bowel cancer: page 4 of 5

5 Bowel cancer: should I be screened? A family history of bowel cancer. This means that a close relative (parent, child, brother, or sister) was diagnosed with bowel cancer before they were 45, or two close relatives were diagnosed with bowel cancer at any age Ulcerative colitis or Crohn's disease. These are long-term diseases that cause inflammation (swelling and irritation) inside the bowel Polyps or bowel cancer in the past. If you've had polyps removed from your bowel in the past, or you've had bowel cancer before, you're more likely to get bowel cancer again Familial adenomatous polyposis. This is a rare disease that runs in families. It causes lots of polyps to grow in the bowel and makes bowel cancer more likely. Where to get more help The NHS Bowel Cancer Screening Programme provides detailed information for patients at This information is aimed at a UK patient audience. This information however does not replace medical advice. If you have a medical problem please see your doctor. Please see our full Conditions of Use for this content. These leaflets are reviewed annually. Last published: Sep 16, 2015 page 5 of 5