Bowel cancer screening

Bowel cancer is one of the most common cancers and a leading cause of cancer-related death. The risk of developing it rises with age, so your chance of bowel cancer is higher from middle age onwards.

Bowel cancer can develop with no symptoms#

The cancer can grow in the bowel for years before spreading to other parts of the body. Because it often causes no symptoms in its early stages, screening is used to look for signs of cancer in people who feel well. If it is detected early, bowel cancer can be successfully treated.

Who is screening for?#

Age is the biggest risk factor for bowel cancer, so screening programs invite people within a particular age range who do not have any symptoms. The age you start, and how often you are screened, depend on the program where you live, but screening is usually repeated at regular intervals (commonly every 2 years).

If you have a family history of bowel cancer, talk to your doctor about which screening options are right for you. Make an appointment with your doctor if you have any symptoms, such as unusual changes in your bowel habits or bleeding from the bowel, whatever your age.

How do I complete the screening test?#

A common screening method is a home test kit that you can do yourself. It comes with detailed instructions and involves taking tiny samples from 2 separate bowel motions (poo). Once you have done the test, you send it back in the mail, and it goes to a laboratory to be analysed.

What happens once I have done the test?#

You usually get your results within a couple of weeks. It is very natural to feel anxious while waiting. It can help to talk to a close friend or relative about how you are feeling.

A negative result#

A negative result means that blood was not detected in your sample. This does not mean you will never get bowel cancer, or that you definitely do not have cancer, because:

• some bowel cancers don’t bleed, or only bleed sometimes
• the test detects most (up to 85%) but not all bowel cancers

This is why it is important to do the screening test at regular intervals. If you receive a negative result but notice symptoms such as unusual changes in your bowel habits or bleeding from the bowel, see your doctor.

A positive result#

A positive result means that blood was detected in your sample. Contact your doctor to discuss the result and obtain a referral for further investigation, which is likely to be a colonoscopy.

The presence of blood in your bowel movement does not always mean you have cancer. There are many possible reasons for blood in your poo, such as:

• polyps
• haemorrhoids
• inflammation of the bowel from conditions such as Crohn’s disease or ulcerative colitis

Even so, you will need further investigation to identify the cause of the bleeding. A colonoscopy may allow:

• the cause of the bleeding to be found
• any polyps to be removed
• a diagnosis of bowel cancer to be confirmed, if applicable

Key points#

• Bowel cancer is one of the most common cancers and a leading cause of cancer-related death.
• The risk of bowel cancer rises with age.
• Bowel cancer can develop with no symptoms.
• Screening helps find cancer early in people who do not have any symptoms.
• Age is the biggest risk factor for bowel cancer.

Where to get help#