To mark World Cancer Day on 4 February 2018, we’re turning our thoughts to an area of our body that most of us would, if we’re honest, probably prefer to ignore.
Our colon is part of our large intestine, the final part of our digestive system. Its function is to process waste products from the body, to reabsorb fluids and to prepare for the elimination of waste via the rectum.
There are four parts to the colon – the descending colon, the ascending colon, the transverse colon and the sigmoid colon. It is also known as the large bowel or large intestine.
Bowel cancer is the general term for cancer that begins in the large intestine. Depending on the precise location of cancer it may be called colon or rectal cancer. It mostly affects people over the age of 60.
The main symptoms of bowel cancer are:
- Blood in the poo that occurs persistently and has no obvious cause. This may be accompanied by a change in bowel habits.
- Persistent change in bowel habits – normally going for a poo more often and having looser poo.
- Lower abdominal pain, bloating or discomfort that occurs after eating. It may be accompanied by loss of appetite or unintended weight loss.
Just because you have these symptoms, it does not mean you have cancer as there can be other causes. For example, blood in the poo can be caused by piles and abdominal pain can be associated with something that you have eaten.
Symptoms of bowel cancer are persistent so it’s a good idea to go to your GP if you have had your symptoms continuously for some time.
However, do not put it off too long as the earlier you are diagnosed the better your chances of survival.
The precise causes of bowel cancer aren’t fully understood but a number of factors are believed to increase your risk of developing the disease. These include:
- Age – almost 9 in 10 cases of bowel cancer occur in people aged 60 or over.
- Diet – the risk of cancer is increased if your diet is high in red or processed meats and low in fibre.
- Weight – bowel cancer is more common in people who are overweight or obese.
- Exercise – lack of exercise is associated with an increased risk of bowel cancer
- Alcohol and smoking – there is some evidence that a high alcohol intake and smoking may increase your chances of getting bowel cancer
- Family history – if you have a close relative (mother or father, brother or sister) who developed bowel cancer under the age of 50, you are at a greater lifetime risk of developing the disease yourself. Discuss this with your GP as regular health screening is offered to people in this situation.
- Other conditions – if you have had ulcerative colitis or Crohn’s disease in the colon for more than 10 years your risk of bowel cancer may be higher.
Not all of these risk factors can be managed. For example, you can’t do anything about a genetic predisposition to the disease. However, there are some steps you can take to minimise other risks. These include:
- Eating a healthy balanced diet, rich in fruit and vegetables
- Avoiding too much red meat
- Cutting down on alcohol
- Stopping smoking
- Taking regular exercise
- Losing weight if you are overweight
Two forms of screening for bowel cancer are offered to adults in England between the ages of 60 and 74:
- FOB (faecal occult blood) tests – every two years adults are sent a home test kit that involves testing a poo sample.
- Bowel scope screening is gradually being introduced for men and women aged 55. A doctor or nurse will examine the lower part of the bowel using a thin flexible instrument to look for polyps. Removing these reduces your chances of developing bowel cancer.