Update on the cost-effectiveness of screening for colorectal neoplasia

Colorectal cancer is an ideal target for population screening because it is a prevalent disease with an identifiable precursor lesion that, when treated, favorably alters the natural history of the disease. Several strategies for screening have illustrated efficacy, including fecal occult blood testing, sigmoidoscopy and colonoscopy. Cost-effectiveness analyses have been performed to determine whether the resources required to implement screening are justified by potential gains. The U.S. Preventive Services Task Force recently commissioned a study on the cost-effectiveness of colorectal cancer screening, which revealed that screening was cost-effective compared to no screening. However, it could not be confirmed which strategy would save the most life-years, nor which was most cost-effective. Since publication of this review, several additional cost-effectiveness analyses have been performed. These studies confirm that screening average risk patients at age 50 by a variety of available strategies is likely to be reasonable by current standards for resource utilization, and that either colonoscopy every 10 years (or once at age 65) or the combination of annual fecal occult blood testing with sigmoidoscopy every 5 years are viable alternatives. Additional economic analyses have examined the use of aspirin chemoprophylaxis to prevent colorectal cancer either alone or as an adjunct to screening strategies. These studies reaffirm the cost-effectiveness of colorectal cancer screening, but illustrate that aspirin chemoprophylaxis is unlikely to be associated with gains for which society would be willing to pay. At present, the decision to choose one colorectal screening strategy over another is based on availability of screening modalities, patient and provider preferences, and associated adherence to screening recommendations. Assessment of preference and development of interventions to increase adherence to screening should be a focus of research in the future.