What is bowel cancer?

The most common cancer in Australia (after skin cancer)

This cancer develops silently over years from uncontrolled, wart-like growths on the inner surface of the large bowel called polyps

Removing pre-cancerous polyps prevents bowel cancer

90 per cent of bowel cancers can be treated successfully, if detected early


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Who is at increase risk of getting bowel cancer?

  • Before 85 years, the lifetime risk is:

1 in 9 for men                1 in 12 for women

  • Risk increases with age
  • Men tend to get it 5-10 years earlier than women
Approximate risk over the next….
If a person is aged 5 years 10 years 15 years 20 years
30 1 in 7000 1 in 2000 1 in 700 1 in 350
40 1 in 1200 1 in 400 1 in 200 1 in 90
50 1 in 300 1 in 100 1 in 50 1 in 30
60 1 in 100 1 in 50 1 in 30 1 in 20
70 1 in 65 1 in 30 1 in 20 1 in 15
80 1 in 50 1 in 25

Bowel cancer risk is higher for people who have:

  • blood passed during a bowel motion
  • changes in bowel habits lasting more than two weeks
  • prior bowel cancer or polyps
  • a family member with bowel cancer or advanced polyps
  • colitis for more than 10 years

Do I need bowel cancer screening if I have no symptoms and no family history? YES

  • Bowel cancer is most common in people with no symptoms and no family history
  • It is Australia’s forgotten, most common, life-threatening but preventable cancer
  • If you wait for symptoms, it may be too late to cure
  • Earlier detection save lives and improves outcome
  • One of the easiest cancers to catch early if screened at a preventable and curable stage (at polyp stage or before symptoms)
  • There are several safe, acceptable and effective screening tests available

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What screening options do I have? – there is no perfect option

Option 1: Faecal Occult Blood Test every 1-2 years (FOBT stool test) +/- one lifetime colonoscopy at 60-65 years old

  • Conveniently done at home, non-invasive, inexpensive, detects “invisible” bleeding of a early stage “silent” bowel cancer
  • proven decrease bowel cancer death by 15-30% if repeated every 1- 2 years over 15 years
  • 1 or 2 negative FOBTs is not an “all clear”. Negative test may still have a cancer or polyps. Must stay in program for over 10 -15 years to be worthwhile
  • positive FOBT = bowel cancer only 3-5%. All positive FOBTs need  colonoscopy to investigate cause.

 Option 2: Colonoscopy every 10 years (starting age: 40 if family history, 50 men, 55 women)

  • most accurate, well tolerated, probably most effective
  • proven decrease bowel cancer death by 50-70%
  • needs bowel preparation, 2-4 hours in day hospital, sedation
  • most costly, 1 in 500 may have a serious complication
  • negative test does not exclude polyps or cancer 100%.

 Option 3: Flexible sigmoidoscopy every 5 years plus FOBT

  • accurate, avoid large volume bowel preparation, no sedation
  • only examines left side of bowel – to decrease risk of missing right-sided lesions do FOBT
  • 1 in 15000 may have a serious complication

Option 4: CT- colonography every 5 years

  • accurate, easy to perform
  • may miss small polyps, needs bowel prep, may be uncomfortable
  • radiation dose = 350 Xrays
  • need colonoscopy for polyps
  • may find irrelevant lesions which requiring followup testing for month/years

Is bowel screening for me?

  • If you are 50 years or over, bowel cancer screening may save your life
  • Australians are being invited to take part in a new Government funded program using the “FOBT every 2 years” option to be fully implemented in 2020
  • currently most (even when offered screening) do not take it up. This is partly why we have not decreased bowel cancer deaths in Australia since the 1960s.
  • Many people who come to a specialist favour colonoscopy every 10 years (or every 5 years if there is a family history). There are also many who go for the less invasive, convenient FOBT stool test at home every year (or two).
  • Screening for bowel cancer, when you feel well, have no symptoms and have no family member with bowel cancer, is a preventative health decision.
  • Other examples include: asking a doctor for a‘flu shot or to check your blood pressure or sugar level for diabetes, or an annual skin check for skin cancers, or for women, a mammogram for breast cancer or pap smears for cervical cancer or, for men a prostate examination
  • Talk your decision over with your doctor. Encourage the people close to you over 50 to do the same. Each option has a set of benefits and risks. None is 100% accurate. Any form of bowel cancer screening may save your life or a loved one and is better than waiting until it is too late.

“Survival from bowel cancer in Australia has not improved since the 1960s.

Don’t die from embarrassment. Screening saves lives.”