The study demonstrates that a five-yearly screening program would save lives, and be cost-effective.
The analysis was performed from a societal perspective, using a Markov model based upon hypothetical subjects representative of the 50-year-old US population at average risk for CRC.
They measured discounted lifetime costs, life expectancy and incremental cost-effectiveness (CE) ratio in 22 different CRC screening strategies.
The best strategy reduces cancer incidence by 60% and CRC mortality by 80%.
In the base-case analysis, compliance was assumed to be 60% with the initial screen and 80% with follow-up or surveillance colonoscopy.
The most effective strategy for white men was annual rehydrated fecal occult blood testing (FOBT) plus sigmoidoscopy (followed by colonoscopy if either a low- or high-risk polyp was found) every 5 years from age 50 to 85 years.
This resulted in a 60% reduction in cancer incidence and an 80% reduction in CRC mortality compared with no screening, and an incremental CE ratio of US$92 900 per year of life gained compared with annual unrehydrated FOBT plus sigmoidoscopy every five years.
Colonoscopy every ten years was less effective than the combination of annual FOBT plus sigmoidoscopy every five years. However, a single colonoscopy at age 55 achieves nearly half of the reduction in CRC mortality obtainable with colonoscopy every ten years.
Because of increased life expectancy among white women and increased cancer mortality among black people, CRC screening was even more cost-effective in these groups than in white men.
In concluding the team stated that screening for CRC, even in the setting of imperfect compliance, significantly reduces CRC mortality at costs comparable to other cancer screening procedures.