WHAT IS BOWEL CANCER AND HOW TO AVOID IT?

1 in 14 men and 1 in 19 women will be diagnosed with bowel cancer during their lifetime – according to  Cancer Research UK so what is it? What causes? And how can you avoid it?

We asked Dr. Sam Rodgers, GP and Medical Director at Medichecks.com:

 

What is bowel cancer?

The bowel has some of the most rapidly reproducing cells in the human body. It does this to replace the topmost layer of cells in the bowel lining that are continually being worn away by the passage of food. The reproduction of cells is tightly controlled by our body to ensure that the supply of new cells will usually match the loss of old cells. Bowel cancer occurs when the DNA controlling this process is damaged and cells start to reproduce in an uncontrolled way, commandeering their own blood supply, and in advanced cases spreading to distant areas of the body. In England, over half of all cases of bowel cancer are diagnosed at a late stage but early diagnosis is vital – the earlier detection of bowel cancer increases the likelihood of survival and of successful treatment.

 

Who is at risk? 

There are many risk factors which can increase the likelihood of bowel cancer developing. These include smoking, eating red meat or processed/preserved meats such as ham or salami, obesity and alcohol. A small number of people inherit genes from their parents which may increase their risk of bowel cancer, however nowadays most of these people are aware of their increased risk and will be undergoing regular colonoscopies to monitor for problems. Sometimes polyps will be found on a colonoscopy; whilst these are not cancerous in themselves some polyps have an increased risk of turning into cancer, so the doctor performing the colonoscopy will usually remove them, so they can be tested. As we age our risk of bowel cancer increases. In younger people the same symptoms will usually suggest other problems such as Crohns disease or ulcerative colitis, however bowel cancer is rare but not unheard of in this group.

 

What are the symptoms? 

The symptoms of bowel cancer are quite varied, so there are a range of signs which can cause concern. One of the key changes to look for is an alteration in your bowel habit towards looser stools or diarrhoea. It is important to note that this is a change from what is normal for you, if you have always had loose stools and there has been no change and no other symptoms then this is less likely to be significant. If blood is also present then this can be a sign of a wide range of possible conditions, from innocent haemorrhoids through to more concerning conditions such as Crohns disease, ulcerative colitis and in some cases bowel cancer. Bowel tumours can trigger weight loss, partly through their direct effect upon the body’s metabolism and partly through decreasing how efficiently the bowel can absorb nutrients. Absorption problems and bleeding into the bowel can cause iron-deficiency anaemia to develop, most people are unaware of this until it starts to cause problems such as shortness of breath and dizziness. If the tumour is sitting near the rectum then it may cause people to feel like they haven’t fully emptied their bowels when they have just been to the toilet.

 

What’s most easy to miss? 

Symptoms often develop slowly with bowel cancer, so it is easy to miss them as the change from week to week is relatively slight. Keeping an eye on your weight on a weekly or monthly basis is a good idea, as unexpected weight loss can be an early sign of many more serious conditions, including bowel cancer. Change in bowel habit to looser stools can also be missed, as it may be misinterpreted as due to a change in diet, or a short-term bowel upset such as food poisoning. If it lasts for 6 weeks or more then it should definitely be discussed with your doctor. Levels of iron and haemoglobin can decrease to quite low levels before they become apparent through symptoms such as dizziness or shortness of breath, so this can be missed in the early stages. Blood in the stool is missed if people do not look for it, which is why it is a good idea to check both your stool and toilet paper to look for signs of blood.

 

Is there an easy test you can do to determine whether you are at risk / have bowel cancer?

There are no perfect tests for bowel cancer, as the effects can vary widely from person to person. The best test is a colonoscopy, but this is invasive and comes with its own set of risks. There are tests you can do which will help to tell you whether you should be seeing your doctor about symptoms that you are experiencing. The most widely used of these is the faecal occult blood test which looks for blood within the stool. The national bowel cancer screening program invites all adults between the ages of 60 and 74 to perform this test every two years. The response rate to this is quite low (around six out of every 10 people invited actually return the test kit), so if you have received a test kit through the post I would strongly recommend that you take the test. Alternatively you can get tested privately, for example Medichecks’ bowel cancer check offers the same test as the national bowel cancer screening program and is useful for people who either fall outside of the age range for the national program, or who would like to test within the two-year interval of the national program. It includes interpretation from a doctor advising whether you need to be concerned about any of the results.