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Macmillan and Cancerbackup merged in 2008. Together we provide free, high quality information for people affected by cancer through our publications, website and phone service. Find out more| .
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Many people worry about getting bowel cancer|, sometimes because one of their relatives has developed the illness. This section explains:
The cause of most bowel cancers is not known. But we do know that some things – called risk factors – can increase our chances of developing cancer. Some risk factors are very likely to cause cancer, whereas others will only very slightly increase our likelihood of getting it.
Having a particular risk factor for cancer, or being exposed to one, doesn’t usually mean that we will definitely get cancer; just as not having it doesn’t mean that we won’t. Smoking is a good example of this. If you smoke, it isn’t certain that you will get lung cancer; just as if you don’t smoke, it’s not certain that you won’t. But smoking will greatly increase your risk of getting lung cancer. Nine out of ten people who develop lung cancer are smokers.
Cancer is very common and nearly 1 in 3 of us will develop it at some time during our lives. This means that most of us will have relatives who have had cancer. Surveys have shown that many people are worried that a history of cancer in their family greatly increases their risk. People often worry that an increased risk of cancer can be inherited, or passed on from one generation to another. In fact less than 1 in 10 cases of cancers (between 5 and 10%) have been shown to be due to a family history of the disease.
Genes| carry the biological information we inherit from our parents. They affect the way our bodies grow, work and look. Changes (mutations) in certain genes can increase the risk of bowel cancer in family members who inherit the genetic change. However, only a small number of bowel cancers are thought to be due to an inherited altered gene (genetic mutation) running in the family.
It is only likely that a genetic mutation that can increase your bowel cancer risk is present in your family, if you have:
Your close relatives are your parents, children, brothers and sisters. They are also sometimes called your first degree relatives.
If your family is like this, and you are worried about developing bowel cancer yourself, you might want to talk to your GP. They will ask you questions about your family history. If your GP thinks there’s a chance that you might have an increased risk of developing bowel cancer because of your family history, they will refer you to a genetic counsellor, family cancer clinic or a cancer specialist.
Everyone in England, when they reach 60 (50 in Scotland), will be invited to join the NHS’s new Bowel Cancer Screening Programme|, and offered a faecal occult blood (FOB) test every two years. The FOB test looks for hidden traces of blood in faeces (bowel motions).
People who seem to be at a higher than average risk of developing bowel cancer may be offered regular screening using a colonoscopy, where a long flexible tube is inserted into the back passage to look at the inside of the bowel. This can help to detect bowel cancer early.
If you only have one elderly relative who has developed bowel cancer, or one case of bowel cancer on each side of your family, this does not significantly increase your risk. If you had one of the bowel cancer genes in your family, then it is likely that more than one relative on the same side of the family would have developed bowel cancer.
It can be a normal reaction to severe illness in the family, or to bereavement, to feel more vulnerable to the same disease. If you can’t stop worrying, you may find it helpful to see a counsellor, who can help you get things back into perspective. You can ask your GP, or call our nurses| for details of a local service. You could also call the Cancer Counselling Trust| to speak to a counsellor.
Mind|, the mental health charity, has published a leaflet called 'How to Stop Worrying'.
Other risk factors in the development of bowel cancer can play a bigger role than family history.
The main risk factor for bowel cancer is age. More than eight out of ten people (83%) who get bowel cancer are over 60.
If you have had polyps (non-cancerous, but abnormal tissue in your bowel) or other chronic bowel problems (for example, ulcerative colitis or Crohn’s disease), you are more likely to develop bowel cancer than people who haven’t had these problems. But it is important to remember that most people with chronic bowel problems don’t develop bowel cancer.
You can’t do anything about your age or medical history, but there are other risk factors, known as lifestyle risk factors, that you can control. It has been estimated that about half (50%) of all cancers diagnosed in the UK could be avoided if people made changes to their lifestyles. These changes don’t mean that you definitely won’t get cancer – but they make it less likely. So here are some things that you might want to consider:
Eating large amounts of meat, fat and salt, and not enough fruit and vegetables increases the risk of developing bowel cancer. Try to eat a healthy diet| that contains more fruit and vegetables and reduce the amount of meat, fat and salt you eat. Drinking plenty of water and fresh fruit juice also helps.
If you don’t do any exercise, this increases your bowel cancer risk. Try to exercise regularly. You don’t need to go to the gym – walking, cycling or gardening done regularly can be enough.
Being overweight increases your bowel cancer risk. Try to maintain a healthy weight.
If you or your children are overweight, unsure about your diet or don’t do much exercise, mention your concerns to your GP. Your GP can give you more information or can help you get specialist support.
Both smoking and drinking a lot of alcohol can increase your risk of developing bowel cancer.
If you smoke, giving up is the healthiest decision you can make. There is now a lot of help available for people who want to give up. Ask your GP for advice, call the NHS Smoking Helpline|.
The European Code Against Cancer recommends that to reduce their risk of developing cancer men should drink no more than two units of alcohol a day and women no more than one unit a day. A unit is half a pint of ordinary strength beer, lager or cider; one small glass (125ml) of wine; or a single measure (25ml) of spirits.
Although making these changes may reduce your risk of developing bowel cancer, they do not guarantee that you won’t get cancer. But all of the above strategies will improve your health generally. You can find more information about bowel cancer prevention from Bowel Cancer UK|.
When it is found early, bowel cancer can be treated very successfully. Unfortunately, the early signs of bowel cancer can vary and are not very clear.
You should see your GP if you have:
Bowel problems are very common, so it is most likely that these symptoms do not mean you have cancer. But it is worth getting them checked out. Don’t be embarrassed to speak to your doctor about your bowel problems. For them, this is all very normal.
Don’t hesitate to go back if the treatment your GP suggests does not help you.
Everyone in England over 60 (50 in Scotland) will be invited to join the national screening programme and have a faecal occult blood (FOB) test once every two years until they reach 69 (74 in Scotland). From 2010 people in England will be invited until they reach 75. People older than this can continue to have regular FOB tests by contacting their GP. The FOB test can detect tiny amounts of blood in the bowel motions that might be caused by a cancer, and people with a positive FOB are invited to have further tests.
The bowel screening programme is gradually being phased in across England and Scotland. Wales and Northern Ireland are watching the roll-out in England and Scotland before starting their own programmes. Announcements about the screening programme can be found at www.cancerscreening.org.uk/bowel| or by calling 0114 271 1060.
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