Understanding colorectal disease and bowel screening – what is the science behind it?

science behind colorectal disease

Colorectal diseases affect the colon or rectum – one of the most significant forms of colon or rectum disease is colorectal cancer. Bowel screening is a non-invasive method of detecting early signs of colorectal disease, including colorectal cancer in the hopes of improving patient outcomes. 

A quick tour of your colon and rectum

Your digestive system starts at your mouth and finishes at your anus. Its main purpose is to help you digest the food you eat and absorb nutrients which your body uses for energy, growth and cell repair. At the end of the process, your body expels waste products from the digestive process as urine and faeces. 

The colon and rectum form a key part of the digestive system. By this stage, most of the digestive process has already happened. Your food has already been broken down in the stomach and small intestine and nutrients have been absorbed with the aid of the gallbladder, pancreas and liver. 

The leftover liquidy mush is then sent to your colon (known as the large intestine or bowel). Your colon absorbs water and breaks down the remaining material through bacteria. It moves what’s left to your rectum, which stores this stool or faeces until you go to the toilet and do a poo. 

How does bowel cancer develop? 

Colorectal cancer is the second biggest cause of cancer deaths in Australia. It develops when the cells lining the wall of the colon or rectum grow in an abnormal or uncontrolled way. 

It usually starts with small growths (polyps) on the bowel wall. Most polyps are harmless but some become cancerous as time goes on.

Bowel cancer develops slowly over many years, which gives us time to catch it at an early stage if we are taking a proactive approach towards our health. That’s where screening comes in. 


How does bowel screening work? 

Bowel screening detects traces of blood in your faeces, which may indicate the presence of colorectal disease. 

There are a few different tests on the market but most require you to handle your faeces, which can be off putting. 

With the ColoVantage® Home test, you simply ‘brush before you flush’. You do a poo, brush the toilet bowl water with the brush we provide, then store a sample of that water on the test card we provide. Once you’ve collected two samples, you send them to us and our laboratory processes your test. 

In the lab, we test your sample using a sophisticated immunoassay that looks for the presence of blood. 

Here are some key statistics you should be aware about our product:

  • The sensitivity of ColoVantage Home has been proven to be 87%. Sensitivity result refers to the test’s ability to correctly detect the presence of human haemoglobin in samples provided. disease. 
  • The Specificity of ColoVantage Home has been proven to be 98%. This Specificity result refers to the test’s ability to correctly detect human haemoglobin within the samples provided.  

Why might there be blood in my test sample? 

Blood might be detected in your toilet bowl for a few reasons. You might:

  • have haemorrhoids (piles) that are bleeding
  • have visible blood in your urine or stool – contact your doctor immediately
  • be having your period (or be a few days either side of it)
  • be showing signs of colorectal disease, which needs further investigation. 

What if my screening test is positive? 

If your test is positive, your doctor may recommend a colonoscopy, a procedure to examine the inside of your rectum and colon. 

While you’re sedated, your doctor inserts a long, flexible tube with a camera on the end and examines the lining of your colon and rectum for signs of bowel disease. 

Following a positive screening test, a colonoscopy can help to: 

What can you do to protect your bowel health? 

A healthy diet and lifestyle can help to reduce the risk of bowel cancer. That includes: 

  • regular exercise
  • reducing or eliminating alcohol
  • basing your diet around wholegrains, vegetables, fruit, beans and nuts
  • limiting your consumption of red meat and processed meat
  • not smoking. 

Another way to protect your bowel health is to take advantage of bowel screening. For peace of mind, order your ColoVantage® Home test today. 

*All information is general and is not intended to be a substitute for professional medical advice.  Always follow directions for use.

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