Bowel cancer screening is one of the most important steps Australians can take to detect bowel cancer early, often before symptoms appear. Bowel cancer, also known as colorectal cancer, can develop slowly over time, and in many cases it begins as small growths called polyps inside the bowel. Not all polyps become cancer, but some can change over the years and develop into bowel cancer if they are not found and removed.
The difficulty with bowel cancer is that early stages may cause no obvious symptoms. A person can feel completely well and still have early changes in the bowel. This is why bowel cancer screening is so important. Screening is designed to look for early signs of bowel cancer in people who do not currently have symptoms.
In Australia, eligible people aged 45 to 74 can access a free bowel screening test every two years through the National Bowel Cancer Screening Program. People aged 50 to 74 are generally mailed a free test kit every two years, while people aged 45 to 49 can request their first free kit through the National Cancer Screening Register.
For many people, the first step is a simple at-home test. If the result is positive, the next step is usually a colonoscopy to find out where the blood has come from and whether there are polyps, inflammation, cancer, or another cause.
Article index
- What is bowel cancer screening?
- Why bowel cancer screening is so important
- Who should do bowel cancer screening in Australia?
- Bowel cancer symptoms you should not ignore
- What does the bowel screening test involve?
- What happens if your bowel screening test is positive?
- Colonoscopy after bowel cancer screening
- Bowel polyps and why they matter
- Are you at higher risk of bowel cancer?
- Bowel cancer screening for people with inflammatory bowel disease
- Bowel cancer in younger adults
- How often should bowel cancer screening be done?
- What if your bowel screening test is negative but you still have symptoms?
- How to improve bowel cancer prevention
- Why choose Direct Endoscopy for colonoscopy after bowel screening?
- When to speak with your GP or request a referral
- Final thoughts
What is bowel cancer screening?
Bowel cancer screening is a test used to look for early signs of bowel cancer before a person has symptoms. The most common screening test used in Australia is a faecal occult blood test, often called an FOBT. The current test used in the national screening program is a faecal immunochemical test, also known as a FIT or iFOBT.
The test looks for tiny traces of blood in a bowel motion. This blood is often invisible, meaning you would not see it in the toilet or on toilet paper. Blood in the bowel motion does not automatically mean someone has bowel cancer. It can be caused by polyps, haemorrhoids, inflammation, diverticular disease, or other bowel conditions. However, because blood can also be an early warning sign of bowel cancer, a positive result should always be followed up properly.
The at-home test is simple. It usually involves collecting small samples from two separate bowel motions and sending them to a laboratory for testing. The test does not diagnose bowel cancer. Instead, it helps identify people who need further investigation, most commonly with a colonoscopy.
Why bowel cancer screening is so important
Bowel cancer is common in Australia. According to Cancer Australia’s bowel cancer statistics, thousands of Australians are diagnosed with colorectal cancer each year. Cancer Australia also reports that bowel cancer remains one of the most commonly diagnosed cancers in Australia.
The good news is that bowel cancer is often treatable when found early. The National Bowel Cancer Screening Program aims to reduce deaths from bowel cancer by detecting early signs of the disease, and the Australian Government states that if bowel cancer is found early, more than 90% of cases can be successfully treated.
Screening matters because it can detect signs of bowel cancer before symptoms appear. It can also lead to the detection and removal of polyps before they have the chance to become cancer. In this way, bowel cancer screening is not just about early diagnosis. It can also play an important role in prevention.
Many people delay doing the test because they feel well, feel embarrassed, or assume they are not at risk. However, bowel cancer can affect people who are fit, active, and otherwise healthy. Feeling well does not rule it out. Completing the test when you are eligible is a simple step that can make a significant difference.
Who should do bowel cancer screening in Australia?
Under the National Bowel Cancer Screening Program, eligible Australians aged 45 to 74 can complete a free bowel screening test every two years. People aged 50 to 74 are generally sent a test kit in the mail every two years. People aged 45 to 49 can request their first free kit through the National Cancer Screening Register, and after completing it, they will continue to be sent a kit every two years.
The program is designed for people who do not have symptoms. This is an important distinction. If you have symptoms such as rectal bleeding, persistent changes in bowel habits, unexplained weight loss, ongoing abdominal pain, or iron deficiency anaemia, you should not wait for a routine screening kit. You should speak with your GP, as you may need a different investigation pathway.
People with a strong family history of bowel cancer, a personal history of bowel polyps, previous bowel cancer, inflammatory bowel disease, or certain genetic conditions may also need screening earlier or more often than the general population. The RACGP colorectal cancer screening guidelines provide guidance for general practice, including different approaches depending on a person’s level of risk.
Bowel cancer symptoms you should not ignore
Bowel cancer screening is mainly for people without symptoms. However, it is still important to know the symptoms of bowel cancer, because not everyone who develops bowel cancer will be within the routine screening age group.
Common symptoms can include blood in the stool or rectal bleeding, a recent and persistent change in bowel habit, narrower stools or changes in stool appearance, abdominal pain or cramping, unexplained weight loss, tiredness, weakness, or signs of anaemia. Bowel Cancer Australia’s symptoms guide lists blood in the stool, persistent bowel habit changes, changes in stool shape or appearance, and abdominal pain or cramping among the symptoms that should be investigated.
Symptoms do not always mean cancer. Many bowel symptoms are caused by non-cancerous conditions, including haemorrhoids, irritable bowel syndrome, infections, diverticular disease, food intolerances, inflammatory bowel disease, or medication changes. However, symptoms should not be dismissed, especially if they are new, persistent, unexplained, or worsening.
Speak with your GP if you notice symptoms such as:
- Blood in your stool or bleeding from the rectum
- A change in bowel habits that continues for more than a few weeks
- Ongoing diarrhoea, constipation, or a feeling that the bowel does not empty properly
- Unexplained abdominal pain, bloating, or cramping
- Unexplained tiredness, weakness, or iron deficiency
- Unexplained weight loss
- A strong family history of bowel cancer or bowel polyps
If you are under 45 and have symptoms, do not assume you are too young for bowel cancer. Bowel cancer is less common in younger people, but it can occur. Bowel Cancer Australia’s information on early-onset bowel cancer highlights that younger people with symptoms should seek medical advice rather than accepting age alone as reassurance.
What does the bowel screening test involve?
The bowel screening test is done at home. It is private, quick, and does not require a hospital visit. The kit includes instructions, collection tools, sample tubes, and a reply-paid envelope. Cancer Council Australia provides a useful overview of how bowel cancer screening works and who is eligible.
The test usually requires small samples from two separate bowel motions. You do not need to collect a large amount. The sample is placed into the collection tube and sent to the laboratory. The laboratory checks for tiny traces of blood that may not be visible.
The test is not painful and does not require bowel preparation. Unlike colonoscopy, you do not need sedation and you do not need to take laxatives beforehand. It is simply a screening tool to help identify whether further investigation is needed.
If your test is negative, it means blood was not detected in the samples. This is reassuring, but it does not guarantee that there is no bowel cancer or bowel disease. No screening test is perfect. This is why the test should be repeated every two years while you remain eligible, and why symptoms should still be discussed with a doctor even after a negative screening result.
If your test is positive, it means blood was detected. This does not mean you definitely have bowel cancer. However, it does mean the result needs to be followed up. A colonoscopy is usually recommended to examine the bowel properly and identify the cause of bleeding.
What happens if your bowel screening test is positive?
A positive bowel screening test can be worrying, but it is important to remember that many people with a positive result do not have bowel cancer. The test detects blood, not cancer itself. Blood can come from several causes, including polyps, haemorrhoids, inflammation, diverticular disease, or other bowel conditions.
However, a positive result should never be ignored. The usual next step is to see your GP, who may refer you for a colonoscopy. A colonoscopy allows a specialist to examine the inside of the large bowel using a thin, flexible camera. If polyps are found, they can often be removed during the procedure and sent for testing.
A colonoscopy is the most useful investigation after a positive bowel screening result because it can identify the source of bleeding and help rule in or rule out serious bowel disease. It can also detect and remove polyps before they become cancerous.
It is generally not recommended to simply repeat the bowel screening test after a positive result as a substitute for colonoscopy. RACGP guidance on colorectal cancer screening in Australia notes that one positive iFOBT is adequate to refer for colonoscopy and that repeating a positive FOBT is not recommended.
Colonoscopy after bowel cancer screening
A colonoscopy is a procedure used to examine the inside of the large bowel and rectum. It is commonly recommended after a positive bowel screening test, or when a person has bowel symptoms that require further investigation.
Before the procedure, you will need to complete bowel preparation. This involves taking a special preparation to empty the bowel so the specialist can see the bowel lining clearly. Good bowel preparation is important because small polyps or changes can be missed if the bowel is not clean. You can read more about the process on Direct Endoscopy’s colonoscopy preparation page.
During the colonoscopy, a thin, flexible tube with a camera is gently passed through the rectum and around the large bowel. Most patients receive sedation, which means they are comfortable and usually do not remember much of the procedure. If polyps are found, they may be removed during the colonoscopy. Tissue samples may also be taken if needed.
After the procedure, you will be monitored while the sedation wears off. You will need someone to take you home, and you should not drive or operate machinery for the rest of the day. Your specialist will explain the findings and whether any follow-up is needed.
For patients in Melbourne, Direct Endoscopy provides colonoscopy services across multiple locations, including Frankston, Hampton, Bayswater, Narre Warren and Rosebud.
Bowel polyps and why they matter
Polyps are small growths that can develop on the lining of the bowel. Many polyps are benign, meaning they are not cancer. However, some types of polyps can become cancerous over time. This process can take years, which creates an opportunity for screening and colonoscopy to detect and remove polyps before they become a more serious problem.
This is one of the key reasons bowel screening and follow-up colonoscopy are so valuable. The goal is not only to detect cancer early but also to find and remove pre-cancerous changes where possible.
If polyps are removed during colonoscopy, they are usually sent to a laboratory for testing. The results help determine whether you need another colonoscopy in the future and how soon that should occur. Some people may need follow-up in a few years, while others may return to routine screening depending on the findings.
Are you at higher risk of bowel cancer?
Anyone can develop bowel cancer, but some people have a higher risk. Risk can be influenced by age, family history, medical history, lifestyle, and certain bowel conditions.
Your risk may be higher if you have a strong family history of bowel cancer, especially if a close relative was diagnosed at a younger age. A personal history of bowel polyps or previous bowel cancer may also increase risk. People with inflammatory bowel disease, including ulcerative colitis and Crohn’s disease affecting the colon, may require more regular bowel surveillance.
Lifestyle factors can also contribute. These include smoking, high alcohol intake, being physically inactive, carrying excess body weight, and eating a diet high in processed meats and low in fibre. Not all risk factors are within your control, but some are. Taking part in screening, responding to symptoms early, and maintaining regular medical care are practical steps that can reduce risk or improve the chance of early detection.
If you are unsure about your risk, speak with your GP. They can assess your family history, symptoms, age, and medical background and advise whether routine screening is enough or whether you should be referred for specialist advice. The RACGP’s colorectal cancer guidance can also help patients understand why different people may need different screening or surveillance plans.
Bowel cancer screening for people with inflammatory bowel disease
People with inflammatory bowel disease, such as ulcerative colitis or Crohn’s disease affecting the colon, may need a more personalised bowel cancer surveillance plan. This is different from routine population screening.
Long-term inflammation in the bowel can increase the risk of bowel cancer in some patients. The level of risk depends on factors such as how much of the colon is affected, how long the condition has been present, the severity of inflammation, family history, and whether there are other associated conditions.
If you have inflammatory bowel disease, it is important to follow the surveillance plan recommended by your gastroenterologist. This may involve colonoscopy at specific intervals, even if you feel well. The standard home bowel screening test may not be the most appropriate tool for your situation, particularly if you already have symptoms or known inflammation.
Bowel cancer in younger adults
Bowel cancer is more common in older adults, but it can occur in younger people. In recent years, there has been growing concern about early-onset bowel cancer, which refers to bowel cancer diagnosed in people under 50.
Bowel Cancer Australia’s early-onset bowel cancer information highlights the importance of prompt investigation for younger people with symptoms, particularly because symptoms can sometimes be mistaken for haemorrhoids, food intolerances, stress, or other less serious causes.
This does not mean every young person needs a colonoscopy. However, it does mean persistent symptoms should be taken seriously. If you are younger than the routine screening age and you have rectal bleeding, persistent changes in bowel habits, unexplained abdominal pain, unexplained weight loss, or iron deficiency, speak with your GP.
You should also tell your GP if you have a family history of bowel cancer or polyps. Family history can change the recommended age to begin screening or surveillance.
How often should bowel cancer screening be done?
For average-risk people who are eligible for the National Bowel Cancer Screening Program, the bowel screening test is recommended every two years. The National Cancer Screening Register states that eligible people aged 45 to 74 can do the screening test every two years, with people aged 45 to 49 able to request their first free kit and people aged 50 to 74 able to request a replacement kit if their automatic kit has not arrived, has been damaged, misplaced, or expired.
If you have symptoms, a family history, previous polyps, inflammatory bowel disease, or another risk factor, your doctor may recommend a different approach. This might involve earlier screening, colonoscopy, or specialist review.
It is important not to assume that one normal test means you never need to screen again. Bowel cancer can develop over time. Regular screening increases the chance of finding changes early.
What if your bowel screening test is negative but you still have symptoms?
A negative test means no blood was detected in the samples tested. This is reassuring, but it does not completely rule out bowel cancer or other bowel conditions. If you have symptoms, you should still speak with your GP.
This is especially important if symptoms are new, persistent, or unexplained. A screening test is not a replacement for medical assessment. Symptoms may require blood tests, stool tests, imaging, colonoscopy, or specialist review depending on your situation.
For example, rectal bleeding should not be ignored simply because a screening test was negative. Similarly, persistent changes in bowel habits, unexplained iron deficiency, or unexplained weight loss should be assessed by a doctor.
How to improve bowel cancer prevention
Bowel cancer screening is one part of bowel cancer prevention. Lifestyle also plays a role. While no lifestyle choice can guarantee prevention, healthy habits can help reduce risk.
A bowel-friendly lifestyle generally includes eating a balanced diet with plenty of vegetables, fruit, legumes, and wholegrains; limiting processed meats; staying physically active; maintaining a healthy weight; reducing alcohol intake; and avoiding smoking. It is also important to participate in screening when eligible and to seek medical advice for symptoms.
For people with a family history or other risk factors, prevention also means following medical advice about surveillance. This may include colonoscopy at intervals recommended by a GP or gastroenterologist.
Why choose Direct Endoscopy for colonoscopy after bowel screening?
If you have received a positive bowel screening test result, or your GP has recommended a colonoscopy because of bowel symptoms, Direct Endoscopy can assist with timely assessment and investigation.
Direct Endoscopy provides specialist gastroenterology and endoscopy services across multiple Melbourne locations, including Hampton, Frankston, Rosebud, Narre Warren, and Bayswater. You can view all Direct Endoscopy hospital locations on the locations page.
A colonoscopy can feel daunting, especially after a positive screening result. Direct Endoscopy’s role is to make the process as clear and comfortable as possible, from booking and preparation through to the procedure and results. If polyps are found, they can often be removed during the colonoscopy. If further treatment or follow-up is needed, your specialist will explain the next steps.
If you would like to learn more about the procedure itself, read Direct Endoscopy’s guide on when to get a colonoscopy and how it works.
When to speak with your GP or request a referral
You should speak with your GP if you have received a positive bowel screening result, have bowel symptoms, have a family history of bowel cancer, or are unsure whether you should be screened.
You should also seek advice if you are aged 45 to 49 and want to request your first free bowel screening kit, or if you are aged 50 to 74 and have not received your kit in the mail. You can request a free bowel test kit through the National Cancer Screening Register.
If your GP recommends a colonoscopy, they can refer you to an endoscopy clinic for further investigation. Patients can also visit the Direct Endoscopy book online page for more information about appointment options.
Final thoughts
Bowel cancer screening is simple, private, and potentially life-saving. Because bowel cancer can develop without early symptoms, screening gives doctors a chance to detect warning signs before the disease becomes advanced. It can also lead to the removal of polyps before they become cancer.
If you are aged 45 to 74, make sure you understand your screening options. If you receive a bowel screening kit, complete it. If your result is positive, follow it up promptly. If you have symptoms, do not wait for a routine screening test. Speak with your GP.
Early detection can make a major difference. When bowel cancer is found early, treatment is more likely to be successful.