Bowel cancer screening and FOBT
Currently, bowel cancer is the second highest cause of cancer death in Australia. It affects thousands annually, with the risk of developing bowel cancer increasing significantly from age 45, making screening and early prevention crucial.
The majority of bowel cancer begins as a polyp, which is a non-cancerous (benign) growth in the colon wall. The transformation from a polyp to bowel cancer typically takes 5 to 10 years, providing a vital window of opportunity for early diagnosis and prevention.
Fortunately, if caught early, 90% of bowel cancers can be successfully treated, and polyps can be easily removed during a colonoscopy before they develop into cancer. However, if left untreated or undiagnosed, bowel cancer can spread, requiring surgical bowel removal or potentially becoming fatal.
Australia’s National Bowel Cancer Screening Programme (NBCSP) uses an at-home immunochemical Faecal Occult Blood Test (iFOBT) to detect microscopic amounts of blood in your stool that are invisible to the naked eye. In addition to the routine mail-out, test kits can be requested through your GP, ordered via the National Cancer Screening Register (NCSR), or purchased from local pharmacies.
Current Australian Bowel Cancer Screening Guidelines
- Ages 45 to 49: Eligible Australians in this age group can opt into the National Bowel Cancer Screening Programme and request their first free kit directly from the National Cancer Screening Register (NCSR) or via their GP.
- Ages 50 to 74: A free iFOBT kit is automatically mailed directly to your registered Medicare address every 2 years.
- If you have a significant family history of bowel cancer (e.g., a first-degree relative diagnosed with bowel cancer) or a genetic predisposition, you may require screening starting at an earlier age or direct colonoscopy surveillance rather than an at-home FOBT.
Recognising Symptoms of Bowel Cancer
The FOBT is strictly a screening tool for people without symptoms. If you experience any of the symptoms listed below, you should not wait for an FOBT kit. Contact your GP or Sydney Gut Clinic immediately for a clinical assessment and colonoscopy consultation:
- Blood in your stool or toilet bowl
- A persistent change in bowel habits (e.g., loose stools, severe constipation, or increased frequency lasting over 2 weeks)
- Unexplained abdominal pain, cramping, or bloating
- Unexplained weight loss or loss of appetite
- Unexplained fatigue or iron deficiency anaemia (with or without a drop in haemoglobin levels
Treatment and diagnostic procedures
Depending on your risk factors or screening results, a colonoscopy may be recommended as a preventative or diagnostic procedure to visually examine the lining of your large intestine and remove any detected polyps. Prevention and early intervention remain the most effective protection against bowel cancer.
When polyps or early lesions are identified during a colonoscopy, your specialist can often remove them immediately during the procedure (polypectomy). In cases of established or more advanced bowel cancer, multidisciplinary treatment, including specialised colorectal surgery or oncology management, will be arranged.
Preparing for the procedure
Proper preparation is key to ensuring your colonoscopy is accurate and safe, often beginning up to 7 days prior to your procedure with dietary adjustments and bowel prep solutions. During your consultation, our specialist team will outline exact preparation guidelines and advise you on managing your regular medications.
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FAQ
Yes. If you are an Australian resident aged between 45 and 74, you can request a free bowel screening kit. If you are aged 45–49, you can explicitly opt-in and request your free kit online via the National Cancer Screening Register (NCSR). If you are aged 50–74, kits are automatically sent to your address every 2 years, but you can request a replacement kit through the register if yours has expired or been misplaced.
Bowel screening begins with an at-home immunochemical Faecal Occult Blood Test (iFOBT)] to check for invisible traces of blood. If an FOBT is positive, or if you have symptoms or high risk, the gold-standard procedure to evaluate bowel health is a colonoscopy. A colonoscopy allows a gastroenterologist to inspect the entire large intestine and remove polyps on the spot.
Other secondary diagnostic tests may include:
- Faecal Occult Blood Test (iFOBT)
- Flexible sigmoidoscopy
- CT colonography (virtual colonoscopy)
Modern Australian NBCSP kits are simple and non-invasive. You collect 2 tiny samples from 2 separate bowel movements (as close together as possible). For each sample, place a flushable liner over the toilet water, use the collection stick to take a tiny sample of stool (smaller than a grain of rice), insert the stick into the collection tube, and click it shut. Store the completed tubes in a Ziploc bag in the refrigerator (do not freeze) and post them back promptly in the provided reply-paid envelope.
Older guaiac tests (gFOBT) required dietary restrictions, but Australia’s current immunochemical test (iFOBT) specifically detects human haemoglobin. You do NOT need to avoid red meat, vitamin C, iron supplements, or raw vegetables. You can eat normally and take your routine medications prior to completing the test.
An FOBT should be completed once every 2 years for people aged 45 to 74 who do not have symptoms or a strong family history of bowel cancer. If you test positive or experience symptoms at any age, you should undergo a clinical evaluation and colonoscopy rather than repeating the FOBT.