Bowel Cancer
Bowel cancer is the most common internal cancer in WA with more than 1000 people told the news that they have bowel cancer every year. Bowel cancer also causes the second highest number of cancer deaths, after lung cancer.
The Cancer Council understands that bowel cancer affects not only the people diagnosed, but the whole family and the comprehensive services we offer reflect this.
- What is bowel cancer?
- What are the symptoms of bowel cancer?
- What are the risk factors for bowel cancer?
- Is screening available for bowel cancer?
- What is the National Bowel Cancer Screening Program?
- What is "Get behind bowel screening"?
- How can bowel cancer be prevented?
- How is bowel cancer diagnosed?
- What is Digital Rectal Exam (DRE)?
- What is Faecal Occult Blood Test (FOBT)?
- What is a colonoscopy?
- What is a sigmoidoscopy?
- What is a virtual colonoscopy?
- What is a barium enema?
- What treatments are used for bowel cancer?
- What other support services are available?
What is bowel cancer?
The bowel is made up of the colon and rectum and forms the lower part of the gastro-intestinal tract. The colon and rectum form a muscular tube approximately 1.6m long. They deal with all the waste products that remain in the body after food has been digested and absorbed in the small intestine.
Bowel cancer is the growth of abnormal cells in the bowel. These abnormal cells grow and divide faster than normal cells. Bowel cancer usually develops from an existing growth on the inner lining of the bowel or rectum. These growths are called polyps. Many people have polyps, the majority of which are benign (not cancer). However as polyps are an early warning sign for bowel cancer, they need to be removed.
If left untreated, some polyps may become larger and the cells within the polyp may change to become malignant (cancer). When this happens the cancer often ulcerates and bleeds, or may cause a blockage of the bowel. Over time, the cancer is likely to spread through the bowel wall to the blood vessels and lymph nodes, and even to distant organs, especially the liver.
Cancer Council WA has produced a two part video on bowel cancer which can be viewed on our Youtube channel:
Part 1 : The facts about bowel cancer - covers why you need to know about bowel cancer, what bowel cancer is, the main risk factors and how to reduce your risk.
Part 2 : Screening for bowel cancer - explains how to screen yourself for bowel cancer and who is eligible for the Australian National Bowel Cancer Screening Program.
We would like your feedback on these bowel cancer videos. To help us and go in the draw to win a $50 SunSmart voucher, please complete our 5 minute survey.
What are the symptoms of bowel cancer?
Symptoms of bowel cancer may include one or more of the following:
- Bleeding from your back passage or any sign of blood after a bowel motion
- A change in bowel habit (for example, straining to go to the toilet and/or looser bowel motions)
- Abdominal pain and bloating
- Loss of weight for no obvious reason
- Loss of appetite
- Symptoms of anaemia - unexplained tiredness, weakness or breathlessness
It is important to realise that these symptoms do not necessarily indicate the presence of bowel cancer. For example, rectal bleeding may be the result of haemorrhoids or piles. However, if you do have any of these symptoms you should see your doctor promptly. Remember that with many cancers, earlier diagnosis is associated with a greater chance of successful treatment. As cancer progresses, the chances of surviving the cancer decreases.
Many people experiencing symptoms of bowel cancer delay seeing their doctor because they are embarrassed to discuss their symptoms. Unfortunately, this embarrassment may put your life at risk. It is important to put embarrassment aside and seek advice promptly.
What are the risk factors for bowel cancer?
The cause of bowel cancer is still unknown; however research has identified a number of factors that increase the risk of developing bowel cancer. These factors include:
- Age
- Previous history
- Chronic inflammatory bowel disease
- Family history of bowel cancer
- Immediate family with Familial Adenomatous Polyposis (FAP) or Hereditary Non-Polyposis Colorectal Cancer (HNPCC)
- Increased insulin levels and Type 2 diabetes
People who are at increased risk of developing bowel cancer are strongly advised to contact their doctor to discuss regular surveillance options.
- Age. Everyone is at risk of developing bowel cancer, and the risk of developing bowel cancer increases with age.
- Previous history. Polyps are small growths on the inner lining of the bowel or rectum that are quite common. About 1 in 4 people will have had a polyp by the age of 50, and 1 in 2 people will have had them by age 70. People with a history of polyps in the bowel, especially those who have had multiple polyps, have a higher risk of developing bowel cancer. People who have previously recovered from bowel cancer may develop the disease again in other parts of the bowel. If the person was younger than 50 years of age when the bowel cancer was originally diagnosed the risk of developing a subsequent cancer becomes even greater.
- Chronic inflammatory bowel disease. There are two types of chronic inflammatory bowel disease: ulcerative colitis and Crohn’s disease. These are conditions in which the bowel becomes inflamed due to injury, infection or irritation. If this inflammation occurs for long periods of time it causes damage to the lining of the bowel. This damage increases the chances of bowel cancer developing. The risk of developing bowel cancer depends on how badly inflamed the bowel is and how long the inflammation occurs for.
- Family history. A person’s risk of bowel cancer may be increased if one or more of their close relatives have been diagnosed with bowel cancer. However, only 15% to 20% of people with bowel cancer have a history of the disease within their family.
- Two inherited conditions that can increase bowel cancer risk are Familial Adenomtous Polyposis (FAP) and Hereditary Non-Polyposis Colorectal Cancer (HNPCC). Both are very uncommon conditions but can significantly increase the risk of bowel cancer for those who are affected.
- Familial Adenomatous Polyposis (FAP). FAP accounts for less than 1% of all bowel cancers. FAP is caused by a change in a particular region of our DNA, called the APC gene. DNA contains all the information our cells need to make an identical copy of themselves. The change in the APC gene causes multiple polyps to grow in the bowel and these polyps can turn into cancer if left untreated. The polyps commonly start growing during the late teens or early twenties, but may occur at any age. FAP is passed down in families. If a parent has the altered APC gene there is a 50:50 chance a child may also have it.
- Hereditary Non-Polyposis Colorectal Cancer (HNPCC). HNPCC accounts for about 1-4% of bowel cancers. HNPCC, also known as Lynch syndrome, is also caused by an altered gene. HNPCC is characterised by no or very few polyps, which makes the condition hard to diagnose. People with HNPCC often have bowel cancers that develop when they are in their thirties or forties.
- Type 2 diabetes and increased insulin levels. Type 2 diabetes, or non-insulin-dependent diabetes, is a condition in which the body can no longer respond to the hormone insulin. This results in high levels of insulin in the blood, known as hyperinsulinemia. High levels of insulin lead to increased levels of a protein called insulin-like growth factor-1 (IGF-1) in the blood. IGF-1 is a protein that is believed to help cancer cells grow. People with Type 2 diabetes often have the disease long before it is diagnosed and treated. As a result, their bodies are exposed to high levels of IGF-1 for a long time. People with Type 2 diabetes also put on weight (body fat). These two factors therefore increase the chances of people with Type 2 diabetes developing bowel cancer.
Is screening available for bowel cancer?
Screening for cancer means finding the early warning signs of cancer (pre-cancerous changes), or finding early cancer before symptoms develop. Screening does not diagnose the disease but identifies people who need to undergo further tests to determine whether the disease is present. Research has shown that finding bowel cancer early significantly improves the chances of successfully treating this disease.
Because bowel cancer is such a common cancer, an effective population screening program has the potential to significantly reduce the impact that bowel cancer has on the Australian population. However, population screening and early detection of cancer is only beneficial if the benefits of screening outweigh any possible harm.
Before national screening programs are set up careful studies are carried out to make sure that:
- The screening tests can reliably detect abnormal changes
- The screening tests used don't cause too many false alarms
Between November 2002 and June 2004, the Australian Government carried out the Bowel Cancer Screening Pilot Program at three sites – Melbourne, Adelaide and Mackay. The results of this pilot study showed that a National Bowel Cancer Screening program would be feasible, acceptable and cost effective in Australia.
What is the National Bowel Cancer Screening Program?
From 1 July 2008, the National Bowel Cancer Screening Program begins Phase Two and invites people turning 50, 55 and 65 years of age before 31 December 2010.
The National Bowel Cancer Screening Program uses the faecal occult blood test (FOBT) to screen for bowel cancer. This non-invasive test is used to identify blood in a person’s bowel movements, which is a sign that bowel cancer may be present and that further testing is required.
This test is unable to distinguish between blood that has been shed by cancers and blood caused by other problems, such as haemorrhoids. The test looks for blood in the bowel motion, not cancer in the bowel itself. Further tests are required to make a definite diagnosis of cancer.
If you are eligible to participate in the screening program, you will be contacted by mail and sent the FOBT kit, which includes a description of how to complete the test. You will be required to use the small collection stick supplied with the FOBT kit to take a sample of your bowel movement. The sample is placed in one of the plastic tubes supplied with the kit, sealed and sent to a laboratory for testing.
People that test negative will be informed by return post. About 93% of people that are tested are likely to have a negative result.
People who have a positive test will be referred to undergo a colonoscopy. A positive FOBT does not necessarily mean that you have bowel cancer. Only about 5% of people who have the follow-up colonoscopy will have a cancer and about 20% will have a precancerous growth called an adenoma.
For more information about the National Bowel Cancer Screening Program, call 1800 118 868 or visit www.cancerscreening.gov.au
Update - January 2010
Bowel cancer kills more than 4,000 Australians every year, yet nearly all cases can be cured if found early. The Cancer Council strongly supports the national Bowel Cancer Screening Program and is campaigning for its expansion to cover all Australians 50 and over.
Recently it has been reported that "thousands of people" who completed faulty bowel testing kits through the program could face a delayed cancer diagnosis. Based on evidence, of the 4,890 people who returned a positive test using replacement kits, only a small number are expected to go on to be diagnosed with cancers, most of which will be cured if found early.
A positive FOBT result rarely means you have cancer. It means there are signs that should be investigated, usually through colonoscopy. Of the 7,000 Australians who had colonoscopies after returning a positive FOBT through the program, only 63 had a confirmed cancer and 239 a suspected cancer.
Early detection is the key to saving lives and reducing disease. Bowel cancer is usually easy to treat when detected early. The current FOBT screening program identifies double the number of bowel cancers at the early stage, compared with cancers found after reporting of symptoms.
Encouraging more Australians who are eligible to do the test and expanding the current screening program to screen everyone over the age of 50 every two years (currently the test is only available on a one-off basis to 50,55 and 65 year olds), has the potential to save 30 lives a week.
What is "Get behind bowel screening"?
Western Australians are encouraged to Get Behind Bowel Screening by emailing the Government to support extending the screening program to all Australians over the age of 50.
The current screening program only offers one-off screening and is only open to those aged 50, 55 and 65, with five million people missing out on a test that could save their lives.
Help us campaign for free screening for everyone over 50 by visiting www.getbehindbowelscreening.com.au and sending an email to your local Member of Parliament.
How can bowel cancer be prevented?
Bowel cancer is one of the most preventable cancers. Lifestyle risk factors attributing to bowel cancer include obesity, physical inactivity and poor diet.
There are a number of things you can do to help reduce your chances of developing bowel cancer including:
- Be screened for bowel cancer using a Faecal Occult Blood Test (FOBT) every two years after the age of 50
- If eligible take part in the National Bowel Cancer Screening Program
- Get at least 30 minutes or more of moderate intensity physical activity on most days of the week
- Achieve and maintain a healthy body weight
- Eat at least 5 serves of vegetables and 2 serves of fruit every day
- Avoid processed meat and burnt/charred meat and if you eat red meat try and limit your intake to 3 or 4 palmsized serves (65-100g) a week
- If you drink, limit your alcohol intake
- Quit smoking
How is bowel cancer diagnosed?
The following tests are used to help determine whether a person has bowel cancer:
- Digital Rectal Exam (DRE)
- Faecal Occult Blood Test (FOBT)
- Colonoscopy
- Sigmoidoscopy
- Virtual colonoscopy
- Barium enema
What is a Digital Rectal Exam (DRE)?
A digital rectal exam is an examination of the rectum to check for any lumps or swelling. During the examination a doctor feels inside the rectum with a lubricated, gloved finger. The procedure may be uncomfortable but should not be painful. A digital rectal examination by itself is not used to diagnose cancer in the lower bowel.
What is Faecal Occult Blood Test (FOBT)?
A Faecal Occult Blood Test (FOBT) is a simple, non-invasive test that looks for blood in a bowel movement. An FOBT can be done at home and involves taking samples from two or three bowel movements using a test kit. The National Bowel Cancer Screening Program uses an FOBT to screen for bowel cancer. If an FOBT finds blood, further tests are needed, the most common being a colonoscopy.
An FOBT involves using the small collection stick supplied with the FOBT kit to take a sample of your bowel movement. The stick is placed in one of the plastic tubes supplied with the kit, sealed and sent to a laboratory for testing.
People that test negative will be informed by return post. People who have a positive test will be referred to undergo a colonoscopy.
A positive FOBT does not necessarily mean that you have bowel cancer. Only about 5% of people who have the follow-up colonoscopy will have a cancer and about 20% will have a precancerous growth called an adenoma.
What is a colonoscopy?
A colonoscopy is a test that enables your doctor to look at the inside of your bowel. If a polyp or bowel cancer is found, your doctor can remove it immediately during the procedure. Colonoscopy is usually performed as a day procedure. Colonoscopies can also be used as a surveillance test for people at an increased risk of developing bowel cancer, for example if they have a strong family history of the disease.
A colonoscopy is carried out using a colonoscope, which is a long, thin, flexible tube with a built-in light that is connected to a video monitor. The colonoscope is passed into the large bowel through the anus, and the entire length of the colon and rectum is inspected. Any tumours or polyps that are found can be removed at the same time, if they are not too large. A colonoscopy is usually done under sedation. A full anaesthetic is sometimes necessary.
Often colonoscopy is used as a follow-up test for those people who have tested positive to an FOBT, a flexible sigmoidoscopy or a barium enema. Currently, colonoscopy is only used for people thought to be at a higher risk of bowel cancer because the service is expensive and the resources are limited.
Before undergoing a colonoscopy you need to drink a bowel preparation liquid to clean out the bowel. You may need to follow certain dietary restrictions (for up to 2 days before the procedure), fast the day before your procedure and drink a large amount of a special drink. This drink causes watery diarrhoea, which cleans and empties the bowel.
What is a sigmoidoscopy?
A sigmoidoscopy is used to examine the lower part of the bowel, where cancer is more likely to develop. This procedure is used alone or with FOBT. If a precancerous polyp is detected during the procedure, a full bowel examination by a colonoscopy is usually needed.
Sigmoidoscopy is a procedure in which the doctor inserts a flexible or rigid tube into the anus allowing a visual examination of the rectum and lower part of the colon. A sigmoidoscopy should not be painful, although it may be uncomfortable. Some people complain of a ‘bloated’ feeling afterwards. The test usually takes between 5 and 10 minutes.
There are two types of sigmoidoscope – a rigid sigmoidoscope and flexible sigmoidoscope. The rigid sigmoidoscope is a metal or plastic tube about 25 centimetres long with a light at the end. It is best suited for examining the rectum only.
A flexible sigmoidoscope is a shortened version of a colonoscope, but longer than the rigid sigmoidoscope. A flexible sigmoidoscope contains a flexible video system that is directed from the handle to travel through the rectum and the lower part of the colon. It is best suited to examining the rectum and the sigmoid colon. Depending on its length, it may be able to view the descending colon. The upper part of the colon (transverse and ascending colons) cannot be seen with a sigmoidoscope.
The flexible sigmoidoscope provides a more complete view of the lower colon than the rigid sigmoidoscope and usually makes examination more comfortable. The flexible sigmoidoscope generally has replaced use of the rigid sigmoidoscope.
Before a flexible sigmoidoscopy you will be required to drink a bowel preparation liquid to clean out the bowel. You may need to follow certain dietary restrictions (for up to 2 days before the procedure), fast the day before your procedure and drink a large amount of a special drink. This drink causes watery diarrhoea, which cleans and empties the bowel.
What is a virtual colonoscopy?
A virtual colonoscopy uses a special type of x-ray, called a computerised tomography (CT) scan, to build a three dimensional picture of the bowel. A CT scan is a special type of x-ray that gives a three dimensional picture of the body. Virtual colonoscopy is also known as CT colonography. It will show up any growths on the bowel wall. If growths are found, further tests will be needed to determine if the growths are cancer.
What is a barium enema?
This is a special x-ray of the large bowel. Before the x-ray is taken, a white fluid containing barium (a metallic substance) is run into the bowel through the anus. The barium is later run out of the bowel and air is introduced.
Barium shows up under x-ray, so the x-ray pictures will outline the bowel and show any abnormal areas. If any suspicious or abnormal areas are seen, a colonoscopy is usually required.
Before a barium enema you are required to drink a bowel preparation liquid to clean out the bowel. You may need to follow certain dietary restrictions (for up to 2 days before the procedure), fast the day before your procedure and drink a large amount of a special drink. This drink causes watery diarrhoea, which cleans and empties the bowel.
What treatments are used for bowel cancer?
The type of treatment you have will depend on whether or not the cancer has spread or is at risk of spreading. Although nearly all treatments have side effects, most can be effectively managed. Ask your doctor to explain what side effects to expect and how best to manage these.
Treatments for bowel cancer include:
- Surgery. Surgery is the usual treatment for bowel cancer. It involves removing the cancer as well as surrounding tissue to make sure no part of the cancer is left behind. Usually the bowel can be joined together again to restore normal function. If for some reason it cannot be rejoined, an artificial opening (colostomy) for faecal waste is made in the wall of the abdomen. A temporary colostomy can usually be reversed in a few weeks. Less than 5 per cent of people need a permanent colostomy.
Bowel surgery is a major operation with an average hospital stay of 5 to 10 days followed by a recovering period of 4 to 6 weeks. For very early bowel cancers there is usually no need for additional radiotherapy or chemotherapy. For those with larger tumours or whose cancer has spread to the lymph nodes, the best results are often achieved by combining surgery, radiation therapy and chemotherapy. - Chemotherapy. Chemotherapy uses anti-cancer drugs to help destroy cancer cells that may have spread to other areas of your body, but cannot be detected. Chemotherapy after surgery can be an effective treatment to reduce the chance of the cancer coming back. It is usually injected into a vein in the arm. There are other ways of having chemotherapy including tablet form.
- Radiation therapy. Radiation therapy uses x-rays to destroy cancer cells. It is used prior to surgery for cancer in the rectum to reduce the tumour size to make surgery easier. It is also used to decrease the chance of cancer returning at the site. Radiation therapy after surgery is less common nowadays and timing of treatment is different for each individual. Chemotherapy may be used in addition to radiation therapy.
- Complementary therapies. Complementary therapies can work alongside medical treatments and some have been shown to improve quality of life or reduce pain. There is no evidence that these therapies can cure or prevent cancer. It is important to remember that some of these therapies have not been tested for side effects, may work against other medical treatments and may be expensive. Let your doctor know about all complementary therapies you are thinking of using.
What other support services are available?
The Cancer Council WA offers a range of support and information services to help cancer patients, their families and friends.
Our Cancer Council Helpline 13 11 20 is available to answer all of your questions about bowel cancer. You can call 8am-8pm Monday to Friday to speak to one of our experienced nurses.
