Pathways to Improved Detection and Prevention of Colorectal Cancer: Achieving Goals for Australia's Health to 2000

A diet high in fat and alcohol and low in vegetables and fruits increases risk for colorectal cancer. Males smoking hand rolled cigarettes and cigars and pipes are also at greater risk. Interventions to decrease the consumption of red meats, encourage physical activity and increase intake of vegetables and fruit, calcium, whey protein concentrate, insoluble dietary fibre from barley grain and Vitamin E are promising. The results of cost-effectiveness analyses of screening protocols vary. This reflects variations in methodology, costs, protocols, and assumptions. A recent Japanese study incorporates many alternative protocols and compares biochemical and immunological FOBT. There would be great value in replicating this in Australia. It found that the immunological test (IF) offers a cost-effective method. The strategy of IF every two years, followed by colonoscopy if IF tests are positive was the most cost-effective strategy. Screening should commence between the ages of 40 and 45. An Australian study showed that the two most efficient strategies for testing FOBT positive persons were (a) a combination of repeat FOBT, rigid sigmoidoscopy and barium enema and (b) a combination of flexible sigmoidoscopy and colonoscopy. The 1994 guidelines of the Australian Gastroenterology Institute and the Australian Cancer Society do not recommend routine screening for those over 50 who have no symptoms and no special risk factors. However, they do suggest the use of FOBT and/or sigmoidoscopy for those persons aged 50-75 years making an informed request for screening. They also indicate that a positive FOBT must be investigated by colonoscopy or by flexible sigmoidoscopy and double contrast barium enema if colonoscopy is not available. The guidelines could be improved by careful consideration of the Australian findings, and following a replication of the Japanese study in Australia.