Individuals at “average risk” (general population) should start screening with a FOBT (stool test) at least once every two years from the age of 50.
Bowel cancer affected more than 14,200 Australians annually and more than 4,000 die every year from it, making it the second leading cancer killer. At the age of 50 you have approximately a 1 in 100 chance of developing bowel cancer in the following 10 years and by the age of 60 the risk is 1 in 100 in the following 5 years. If you have a family history then these risks are increased.
The majority of bowel cancer (possibly up to 99%) begins in a polyp, which is a benign growth in the colon. The polyp to cancer sequence of development, which may be 7-15 years, gives a potential window of opportunity during which colonoscopy can remove polyps and so prevent cancer or the cancer can be detected while it is still curable.
The National Bowel Cancer Screening Programme (NBCSP) uses a test (FOBT) to detect microscopic amounts of blood in the stool and so helps to target that section of the population who may benefit most from having a colonoscopy. They are an effective way to save lives and studies that prove the tests work.
However, only about 35% per cent of the people who receive the Government sponsored tests post them back.
This should change from 2014, with the federal government expected to actively promote public awareness and participation. "This is a screening program that clearly works”. At present Australians turning 50, 55, 60 or 65 years of age, who hold a Medicare card or DVA card, are invited to take part in the program. The aim is to expand it so all Australians aged 50 to 74 are offered a test every two years.
Those that have a positive stool test should have a colonoscopy. It is apparent that while colonoscopy is effective in reducing deaths from bowel cancer there have been limitations to it’s effectiveness. There has been increasing awareness of the potential for "missed lesions" but there have also been significant developments to help reduce this risk. These developments include improved preparation of the colon, use of high definition wide angle colonoscopes and video equipment, carbon dioxide insufflation of the colon, retro flexion of the endoscope to look behind folds as well as the assessment of withdrawal time and adenoma detection rates by the endoscopist.
Dr Yoganathan has also learned to identify lesions (sessile serrated adenomas) that were previously felt to be innocuous or innocent but we now realise that they do identify patients at increased risk of subsequent malignancy. Dr Yoganathan has incorporated all these developments into the practice of colonoscopy.
All Australians at the age of 40 years should talk to their doctor about the screening options to prevent bowel cancer.Calculate your bowel cancer risk profile (External Website).