A recent survey in the UK revealed a shockingly low level of awareness of bowel cancer, especially for a nation where bowel cancer is the second biggest cancer killer and claims more than 1,350 lives a month, often because victims are diagnosed too late.

National charity Bowel Cancer UK, who released the results of their survey on 1 April, at the start of UK’s Bowel Cancer Awareness month, found that more than half of two thousand people they surveyed could not name a single symptom of bowel cancer.

Deborah Alsina, Chief Executive of Bowel Cancer UK, told the press that:

“The results of this survey highlight the shocking fact that public awareness of bowel cancer, in terms of its prevalence and its signs and symptoms, is alarmingly low.”

“We know that unlike breast, ovarian and cervical cancers which have received significant public attention, bowel cancer has a very low profile and there continues to be a general reluctance to talk about it openly or to be associated with it in the same way as these other diseases,” she added.

Bowel cancer, which is also known as colorectal cancer, is cancer of the colon and the rectum. The colon is the last stage of the digestive system, after the small intestine has extracted most of the nutrients from food that has been through the stomach. The bacteria-rich colon extracts mostly water, salt and some vitamins, before the solid waste then moves to the rectum to await evacuation. The rectum, which is about 12 cm long, is the final section of the bowel, just before the anus.

In the UK, bowel cancer is the one of the top three most common cancers diagnosed in both men and women, yet nearly three quarters of the women included in the survey did not recognize the disease as being one of the three most prevalent cancers in women.

Alsina said there is a need to raise the profile of bowel cancer as a leading cancer concern in the UK, so everyone is aware of the symptoms and visits their GP if they have had the symptoms for four weeks or more.

If you have any of the following symptoms for more than three or four weeks, you are advised to talk to your GP – it could save your life:

  • Changes in bowel habits, for example loose stools, diarrhoea, constipation, or change in rhythm such as going more or less often than usual.

  • Blood in the stools or bleeding from your bottom or anus.

  • A pain or lump in your abdomen or belly area.

  • Loss of weight, and/or feeling tired, fatigued for no apparent reason.

People often put off going to the doctor about such symptoms, perhaps they feel embarassed, or they don’t want to consider the possibility they might have cancer, or they think it is nothing serious and feel a bit foolish about raising it with their GP.

In fact, problems of the bowel (the colon and the rectum) are common, and in most cases, the symptoms are not of bowel cancer.

So better to go and feel a bit foolish or brave the fear, in the knowledge that it is best to rule bowel cancer out first and not last.

This is because bowel cancer is highly treatable if caught in the early stage, so much so that about 90% of patients whose bowel cancer is diagnosed before the cancer has spread beyond the lining of the bowel, live for at least five years.

The longer a patient leaves it before seeking a diagnosis, the more likely it is, if they have bowel cancer, that the cancer will have spread to other parts. Survival rates are much lower when bowel cancer is diagnosed in the later stages.

2005 people selected at random (852 men and 1,153 women) completed the online Bowel Cancer UK survey between 26th and 31st January 2011.

The charity highlighted the following results in a statement:

  • The most mentioned symptom by respondents who were able to name at least one, was blood in the stools followed by change in bowel habit.

  • A third of of the people surveyed knew someone with bowel cancer.

  • Men and women over the age of 40 were more likely to name one symptom than younger respondents, which is encouraging from the point of view that age is a risk factor for bowel cancer: the older you are the more likely you are to develop the disease.

  • More than half of men and women recognized that bowel cancer is one of the three most common cancers in men, but nearly 60% of respondents incorrectly put testicular cancer in the top three male cancers.

  • Only 23% of respondents identified bowel cancer as one of the three most common cancers in women and only 27% identified it as one of the most common causes of cancer deaths in women.

  • Although female respondents correctly recognized breast cancer as the most common cancer in women, they did not put bowel cancer in the top three: they thought they were at greater risk of developing cervical or ovarian cancer than bowel cancer.
    (This is in sharp contrast to the facts. In the UK, about 17,900 women are diagnosed with bowel cancer every year, compared to just over 2,800 that find out they have cervical cancer and 6,500 that find out they have ovarian cancer.)

In most cases of bowel cancer, we don’t know exactly what causes it, although a recent Spanish study of intestinal stem cells and the genes that control them may give some new clues. That study supports an emerging idea that cancer growth is organized as a hierarchy, such that only “tumor stem cells” have the ability to start and propagate it.

We do know that middle-aged and older people are at much higher risk than younger people. Also, while in 90% of cases people have no particular family history of the disease, for the rest, family history and certain medical conditions can increase the risk of developing the disease. And there is increasing evidence that so-called modifiable factors such as diet, lifestyle, exercise, obesity and alcohol can also play a role.

Age

Although bowel cancer can develop in men and women of any age, the risk is considerably greater in middle-aged and older people.

In the UK, about 97% of bowel cancers are diagnosed in people over the age of 50.

Polyps

Most bowel cancers start in polyps, fleshy lumps that grow out from the inside lining of the colon. Polyps are not uncommon and the chance of having them increases with age: about 1 in 4 of us is likely to have them once we are over 50 and about 1 in 2 when we are over 70. But the good news is that only a small fraction of polyps become cancerous.

Family History and Inherited Conditions

Having a strong family history of bowel cancer raises a person’s risk of developing the disease. So if you have several relatives on the same side of your family diagnosed with bowel cancer, or one or more diagnosed at a young age, you are advised to have a word with your GP. He or she may refer you to a geneticist.

You may also be at higher risk if there are cases of bowel cancer occuring with endometrial, ovarian, stomach, pancreatic and biliary or kidney cancer in your family.

People of Ashkenazi Jewish blood also have a higher risk of bowel cancer.

About 1 in 20 people who develop bowel cancer get it because it is passed down through their genes due to inherited conditions called familial adenomatous polyposis (FAP), where a lot of polyps grow in the bowel, and hereditary non-polyposis colorectal cancer (HNPCC or Lynch syndrome), where bowel cancer develops at a young age, sometimes in more than one place in the bowel.

Other Medical Conditions

Having inflammatory bowel diseases such as very severe ulcerative colitis or Crohn’s disease for many years increases a person’s risk of bowel cancer. Having diabetes and certain other medical conditions also increases the risk, but we don’t know why.

Having had bowel cancer before also raises the risk, as does having had cancer of the uterus, testicle, or lymphoma.

Diet and Lifestyle

Evidence that diet and lifestyle affects a person’s cancer risk is increasing. A diet high in saturated fat, red or processed meat, and low in fibre increases the risk. Low in fibre means a diet low in wholegrains, fruit and vegetables.

Obesity and insufficient exercise also increases the risk, as does drinking too much alcohol. A recent European study found that obese men were about 50% more likely to develop bowel cancer than men of normal weight. The risk is more closely linked to shape (carrying weight more around the waist) than to Body Mass Index, the commonly used measure of obesity that divides a person’s weight in kilos by the square of their height in metres.

There is evidence that an active lifestyle reduces risk of bowel cancer. American researchers who analyzed 20 studies on exercise and bowel cancer found that regular physical activity can reduce by up to 3 times the risk of developing polyps in the bowel.

The researchers, who analyzed studies from the International Agency for the Research of Cancer, the World Health Organisation, 2002 and the World Cancer Research Fund, among others, reported the results of their analysis in the British Journal of Cancer.

They found that together, the studies show that regular physical exercise reduces the risk of developing polyps by 16%, but more crucially, that it reduces the risk of developing advanced or large polyps by 30%.

The researchers weren’t able to say exactly how exercise does this, but they suggested it could be to do with insulin levels in the blood, improved immune function, and higher levels of Vitamin D (when the exercise occurs outside).

Public screening programs are another way to extend survival by finding people with bowel cancer before they develop advanced symptoms, as a recent report from Cancer Research UK suggests.

Figures in that report show that since a screening programme for bowel cancer was rolled out across England, rates of detection of the disease among the target group of people aged 60 and over have gone up, showing it is being found earlier.

The report shows that rates of bowel cancer among people aged 60 to 69 went up by more than 12% in England between 2006, when the new screening programme started rolling out, and 2008.

The programme is based on people using special kits to collect stool samples at home and send them to labs that test for hidden blood (faecal occult blood, FOB) , an early sign of colorectal cancer.

Cancer Research UK said only 2 out of every 100 people tested are likely to receive a positive FOB result, and even if they test positive, it does not mean they have cancer, but should go for further tests. This usually means a colonoscopy to look inside the bowel and find the cause of the bleeding.

Screening is now offered to men and women between the age of 60 and 74 in England.

Managing your risk of bowel cancer, looking out for symptoms and going to the GP straight away if you have any concerns could save your life. Passing the message onto others could save theirs.

And a good way to pass on the message is to invite your friends and family to view “The Bottom Line”, an award-winning 3-minute video from Bowel Cancer UK, which aims to raise awareness of symptoms and the importance of early diagnosis.

Sources: Bowel Cancer UK, Beating Bowel Cancer UK, Cancer Research UK, National Cancer Institute (US), medicinenet.com, Bowel and Cancer Research, “Physical activity and risk of colon adenoma: a meta-analysis”, K Y Wolin, Y Yan and G A Colditz, in British Journal of Cancer, 1 March 2011, 882-885 (doi:10.1038/sj.bjc.6606045).

Written by: Catharine Paddock, PhD