Colorectal cancer is a major cause of cancer deaths in New Zealand, yet most cases are preventable.
Colonoscopy and polypectomy can interrupt the adenoma/carcinoma sequence but is currently only recommended as a surveillance procedure for those with a greater than three times average risk assessed by family history. Only 3% of the population will meet these criteria and this will have little impact on the incidence of colorectal cancer nationally.
Most of the cases of colorectal cancer in New Zealand occur in average risk individuals. Screening for the average risk New Zealander (80% of us) or for those with a single first degree relative over 55 years (17% of us) is not advocated by the National Health Committee working party. They have not recommended the use of any screening modality (FOB testing, flexible sigmoidoscopy, double contrast barium enema or colonoscopy) because of poor sensitivity of some of the tests, the perceived risks of colonoscopy and resource issues relating to the provision of colonoscopy services. These guidelines are likely to be adopted by the district health boards for public hospital screening.
What then are we going to offer the individual who requests screening but does not meet national guidelines? Advanced neoplasia (high grade polyps) are found in 5 to 10% of asymptomatic individuals over 50 years of age undergoing primary screening colonoscopy. Lower grade polyps are found in 20 to 30%.
BowelCheck is an initiative taken by the private healthcare sector. It will provide information and a process for accessing screening procedures for those who wish to assess their own risk directly, by undergoing colonoscopy after they reach an appropriate age, usually 50 plus years.
Visit our website www.bowelcheck.co.nz where there is more detailed information for you and your patients.