Australia performs over 900,000 colonoscopies a year. Fewer than 4% of those done because of symptoms end in a bowel cancer diagnosis.
That gap matters. It means a referral for “further investigation” is not a cancer verdict. It’s a normal step to rule things out as much as rule them in. But if you’ve just been handed that referral, the space between appointment and answer can feel anything but normal.
Here’s what’s actually happening on that pathway, and why it moves the way it does.
What happens after your GP consultation
In a majority of cases your GP doesn’t move straight to colonoscopy. They start with a conversation about your symptoms, your family history, sometimes a physical examination. Stool and blood tests are common from here too.
If anything requires a closer look, your GP refers you to a specialist. Bowel cancer is Australia’s fourth most common cancer diagnosis and second leading cause of cancer death, so GPs take symptoms of it seriously even though most patients won’t turn out to have cancer.
A referral means your symptoms deserve further investigation. It doesn’t mean your doctor expects the worst, less than 2 in a 100 referrals lead to a cancer diagnosis.
Understanding the bowel cancer diagnostic pathway
Colonoscopy is the gold standard for diagnosing bowel cancer. It’s the only test that lets a specialist examine the entire bowel and remove suspicious polyps in the same sitting.
It’s also why the system is under pressure. Referral demand is forecast to grow 7 to 10% annually through to 2030, and median public hospital wait times for colonoscopy already exceed 84 days in many areas, which is against a national target of 30 days for urgent cases. Of the roughly 15,000 bowel cancers diagnosed in Australia each year. Approximately 90% are found because someone raised symptoms with their GP and was referred on.
That’s what makes early, honest conversations with your GP so important. Symptom-led referral catches the majority of bowel cancers.
Why diagnosing bowel cancer isn’t always straightforward
Bowel symptoms rarely point to one cause. Bleeding, bloating, fatigue and changed bowel habits also show up in haemorrhoids, irritable bowel syndrome and diverticular disease.
That’s exactly why a faecal occult blood test (also known as FIT or FOBT) alone isn’t the end of the story for someone with ongoing symptoms. This test can flag that something needs investigating, but it can’t tell your doctor what that something is. Working out the cause usually means combining your symptom history, blood tests, and ultimately, a direct look at the bowel with a colonoscopy.
Getting a diagnosis can take time. Your care team is working hard through a process designed to get the right answer. However the waiting period can be difficult to endure.
What if you’re waiting for a colonoscopy?
If you’ve been referred for a colonoscopy and you’re on a waitlist, you’re not alone. This is where many Australians find themselves, referred but not yet seen, which can be of concern.
A few things are worth knowing while you wait.
Your GP may prioritise you. If your symptoms worsen or new symptoms develop, go back to your GP. Referrals can be upgraded to urgent status. Don’t assume that because you’ve been referred, nothing more can be done.
A FIT test may already have been done. A Faecal Immunochemical Test (FIT) shows the presence of small amounts of blood in the stool. If you’ve had a FIT, and it came back negative, that’s reassuring. However, if it is positive, this could indicate several bowel diseases including cancer.
Other triage tools now exist.
If a blood test option like this is relevant to your situation, it’s worth asking your GP about it.
Why some patients delay bowel cancer investigations
Embarrassment and fear are two of the most common reasons people put off raising bowel symptoms, or delay following up after a referral. Some people are also simply reluctant to handle a stool sample for a faecal test, and put off testing altogether.
That hesitation is understandable. Bowel symptoms are personal, and the fear of invasive investigations and what it might find can feel bigger than the symptoms themselves.
But the numbers tell a different story to the one most people fear. The vast majority of people investigated for bowel symptoms do not have cancer. And for the minority who do, finding it earlier is what gives treatment the best chance of working. When bowel cancer is detected early, five year survival rates are over 90%.
Raising symptoms early gives you and your doctor more options, not fewer.
If you’re on this pathway now
Most people referred for further investigation will not receive a serious diagnosis. That’s worth remembering while you wait.
Stay in touch with your GP. Ask questions at every step, including whether a blood test option like ColoSTAT® could be relevant to your situation. And if bowel symptoms have been on your mind but you haven’t raised them yet, this is the week to make that appointment.
For support and information while you wait, Bowel Cancer Australia has resources built for exactly this stage of the journey.
