Endoscopic colorectal cancer screening: a cost-saving analysis

Background: Comprehensive analyses have shown that screening for cancer usu ally induces net costs. In this study, the possible costs and savings of en doscopic colorectal cancer screening are explored to investigate whether th e induced savings may compensate for the costs of screening. Methods: A sim ulation model for evaluation of colorectal cancer screening, MISCAN-COLON, is used to predict costs and savings for the U.S. population, assuming that screening is performed during a period of 30 years. Plausible baseline par ameter values of epidemiology, natural history, screening test characterist ics, and unit costs are based on available data and expert opinion. Importa nt parameters are varied to extreme but plausible values. Results: Given th e expert opinion-based assumptions, a program based on every 5-year sigmoid oscopy screenings could result in a net savings of direct health care costs due to prevention of cancer treatment costs that compensate for the costs of screening, diagnostic follow-up, and surveillance. This result persists when costs and health effects are discounted at 3%, The "break-even" point, the time required before savings exceed costs, is 35 years for a screening program that terminates after 30 years and 44 years for a screening progra m that continues on indefinitely. However, net savings increase or turn int o net costs when alternative assumptions about natural history of colorecta l cancer, costs of screening, surveillance, and diagnostics are considered. Conclusions: Given the present, limited knowledge of the disease process o f colorectal cancer, test characteristics, and costs, it may well be that t he induced savings by endoscopic colorectal cancer screening completely com pensate for the costs.