Bowel cancer is the second most common form of cancer in Australia, after non-melanoma skin cancer. And it's becoming more common - according to the Cancer Council, more than 13,500 new cases are diagnosed each year.
But there are steps you can take to prevent and detect bowel cancer. The following information may help you do this by looking at symptoms to keep an eye out for, causes of bowel cancer, preventive measures to decrease your risk, screening services that help detect bowel cancer and where to find out more.
What is bowel cancer?
Bowel cancer happens when cells in part of the bowel (the intestines) grow abnormally and form a lump or tumour, often called polyps. You may have heard of bowel cancer referred to as 'colon cancer' or 'colorectal cancer'. This is because most bowel cancers are in the large bowel, made up of the colon and the rectum. The colon and the rectum are part of your digestive system and are responsible for absorbing water and nutrients from food then helping your body get rid of the waste.
What are the symptoms?
Bowel cancer isn't always obvious in its early stages, but symptoms to look out for include:
- blood in bowel motions. If bright red blood shows up in your stools, you'll usually be sent for further tests. Blood can be hard to detect but you can now get access to sensitive tests, so talk to your GP to find out more.
- unexplained anaemia. This may be caused by the symptom mentioned above, leading to too few red blood cells or not enough haemoglobin in your blood.
- changes in bowel habits. Look out for a sudden onset of constipation, diarrhoea or the feeling of incomplete emptying of the bowel that continues for several weeks.
- abdominal pain, bloating or cramping. If you notice pain, or a lump or swelling in your belly, talk to your GP who might suggest further testing.
More general symptoms include:
- weight loss for no obvious reason and/or loss of appetite
- tiredness or breathlessness for no apparent reason.
What are the causes?
The causes of bowel cancer aren't fully understood . Ageing appears to be a major factor — by 85 years of age, 1 in 10 men and 1 in 14 women will be diagnosed with bowel cancer. Most often it affects people over 50 but it can occur at any age. It's also slightly more common in men than in women.
Your risk of bowel cancer increases if you have:
- a family history of bowel cancer. If one or more of your close relatives (a parent, sibling or child) has had bowel cancer, it doesn't necessarily mean that you' ll get it . But you' re more likely to get it than those without a family history.
- an inherited bowel condition. There are two inherited conditions that can increase your risk — familial adenomatous polyposis (FAP) and hereditary non-polyposis colorectal cancer (HNPCC), the latter also known as Lynch syndrome.
- a long-term bowel condition. This includes conditions such as Crohn's disease or ulcerative colitis.
- diabetes.
The following environmental and lifestyle factors may also increase your risk :
- A diet low in fibre, fruit and vegetables and high in red and processed meat
- An inactive lifestyle
- Being overweight or obese
- Being a smoker.
What can I do to lower my risk?
Considering the lifestyle factors listed above, you may be able to reduce your risk of bowel cancer by:
- eating a healthy high-fibre diet
- exercising regularly
- maintaining a healthy body weight
- not smoking.
Eating a variety of fruit and vegetables, reducing saturated fats (in animal products, processed foods and takeaway), and cutting down on processed and red meat can help you maintain a healthy bowel. There's strong evidence that eating fibre can help prevent bowel cancer by reducing the risk of problems such as constipation and inflammation of the bowel wall . The National Health and Medical Research Council (NHMRC) recommends adult women have at least 25g fibre a day, and adult men at least 30g. Find out more about fibre.
Evidence also suggests that regular exercise may reduce your risk of bowel cancer. According to the Cancer Council of Australia, physical inactivity is an important risk factor responsible for 14 percent of bowel cancers. While the National Physical Activity Guidelines recommend adults take at least 30 minutes of moderate-intensity exercise most days of the week, the Cancer Council recommends you aim for 60 minutes a day of moderate activity. Although 60 minutes of exercise a day may seem daunting at first, you may find it easier to start with 30 minutes a day, even in two to three sessions of 10-15 minutes each, and keep increasing the time you spend exercising as your fitness improves until you reach that goal. This level of physical activity, along with an appropriately sized and healthy diet, can help you achieve and maintain a healthy weight and lower your risk of cancer. Read more about the benefits of exercise.
What about early detection?
If you have bowel cancer, early detection provides the best chance of cure. According to the Cancer Council, 90 percent of bowel cancer can be treated successfully if it's found early.
Talk to your GP about having regular bowel examinations if you're already at an increased risk of bowel cancer because you or your family has been directly affected by :
- multiple polyps in the bowel (known as familial a denomatous polyposis coli FAP), which causes about one percent of bowel cancers
- hereditary non-polyposis colorectal cancer (HNPCC), which is responsible for about five percent of all bowel cancers
- conditions involving fewer bowel polyps, which may or may not be pre-cancerous. Usually, your doctor will recommend that such polyps are removed.
The NHMRC recommends bowel cancer screening for people aged 50 and over who have an average risk of developing bowel cancer, as research has shown that this risk rises significantly from the age of 50. Screening is usually carried out through a faecal occult blood test (FOBT), which can detect blood in your stool.
What screening programs are available?
The Australian Government's National Bowel Cancer Program, which currently offers free FOBT kits to eligible Australians who turn 50, 55 or 60 years of age between January 2011 and December 2014.
If you' ve been invited to participate in the program but you're unsure about taking part, talk to your GP about whether or not you need bowel cancer screening.
If you're not eligible to participate in the program but you' re interested in bowel cancer screening, speak to your doctor or pharmacist about other ways to get a FOBT kit.
From time to time, community or consumer organisations like Rotary or Bowel Cancer Australia run screening programs through pharmacies. This usually involves a simple test that you can take home and send to a laboratory for analysis. The test results are then sent back to you and your doctor.
A positive FOBT result doesn't necessarily mean you have bowel cancer. It may have just detected blood in your stools, which can be an early warning sign. A person with a positive FOBT is 12 to 40 times more likely to have bowel cancer than a person with a negative test.
What happens if I receive a positive result in my screening test?
If your screening test returns a positive result, visit your GP within the following two weeks to discuss your next steps. Usually, your GP will try to find out if you've experienced symptoms that may indicate bowel cancer. They'll also pay attention to your family medical history. They may then recommend further testing which can include:
- a barium enema followed by X-rays. Barium is a metal that helps illuminate the digestive organs for an X-ray.
- an examination of the rectum and lower part of the bowel. This is where a sigmoidoscope (a tubular probe with a light on the end ) is inserted into the rectum and lower part of the bowel. The specialist may also take a small sample of cells (known as a biopsy) from your bowel during the procedure and examine them under a microscope.
- a colonoscopy. This test involves a long, flexible tube being inserted into the rectum and the bowel. A positive colonoscopy might show an adenoma (a tumour of the glands) or cancer.
How is bowel cancer treated?
The type of treatment you receive depends on the size of the cancer, whether it has spread, your current general health, and your own personal concerns and requirements . You can discuss treatment options with your GP and any specialists involved in your care.
The most common treatment is surgery to remove the tumour and surrounding bowel tissue. This ranges from a polypectomy (to remove malignant polyps) to a partial or - more rarely - a full colectomy (removing a section of the colon).
If the bowel cancer has spread to other parts of your body, treatment may not be effective in curing it. But it's likely you can keep the cancer under control for a long time, depending on:
- where and how far the cancer has spread
- what treatment you've had in the past
- the type of bowel cancer.
Treatment for controlling bowel cancer includes surgery, chemotherapy, immunotherapy, pain- relieving drugs or a combination of the above. There is good evidence that chemotherapy or radiotherapy - or increasingly, both - will reduce the chance of cancer returning. If you've had surgery higher up in the bowel, sometimes a stoma (colostomy bag) is temporarily attached outside the abdomen to capture your stools while your wound heals .
Further information
Cancer Council Australia
The Helpline (13 11 20) connects you to your local state or regional Cancer Council centre, where experts can answer your questions and tell you about services and local support.
www.cancer.org.au
Bowel Cancer Australia
www.bowelcanceraustralia.org
Rotary National Bowelscan
www.nationalbowelscan.org.au
Sources
Cancer Council Australia. Colorectal cancer. [online] Surry Hills, NSW [last updated 19 May 2011, accessed 17 Jun 2011] Available from: http://www.cancer.org.au//aboutcancer/cancertypes/colorectalcancer.htm
Cancer Council Australia. Move your body. [online] Surry Hills, NSW [updated 31 Aug 2009, accessed 11 Aug 2010] Available from: http://www.cancer.org.au/Healthprofessionals/patientfactsheets/Lifestyle/Move_your_body.htm
Cancer Council NSW. Bowel Cancer Screening and Testing - Making Individual Choices. [online] Kings Cross, NSW: Cancer Council. [accessed 17 Jun 2011] Available from: http://www.cancercouncil.com.au/html/prevention/checkup_screening/downloads/bowel_cancer_Screening_factsheet.pdf
Cancer Council NSW. Position statement: Fibre, wholegrain cereals and cancer prevention. [online] Kings Cross, NSW: Cancer Council. Nov 2008 [accessed 4 Aug 2010] Available from: http://www.cancercouncil.com.au/html/healthprofessionals/nutrition_physical/downloads/positionstatement_fibre_wholegraincereal.pdf
Department of Health and Ageing. National Bowel Cancer Screening Program. [online] Canberra, ACT: Commonwealth of Australia. [last updated 17 Jun 11, accessed 17 Jun 2011] Available from: http://www.health.gov.au/internet/screening/publishing.nsf/Content/bowel-about
National Health & Medical Research Council. Nutrient Reference Values - Dietary Fibre. [online] Canberra, ACT: Commonwealth of Australia. c2009 [accessed 4 Aug 2010] Available from: http://www.nrv.gov.au/nutrients/dietary%20fibre.htm
National Health & Medical Research Council. Clinical Practice Guidelines for the Prevention, Early Detection and Management of Colorectal Cancer. [online] Canberra, ACT: Commonwealth of Australia. 2005 [accessed 17 Jun 2011] Available from: http://www.nhmrc.gov.au/publications/synopses/cp106/cp106syn.htm
Last published: 30 July 2011
