Cost-effectiveness of microsatellite instability screening as a method fordetecting hereditary nonpolyposis colorectal cancer

Background: The National Cancer Institute has published consensus guideline s for universal screening for hereditary nonpolyposis colorectal cancer (HN PCC) in patients with newly diagnosed colorectal cancer. Objective: To determine the cost-effectiveness of screening compared with s tandard care in eligible patients with colorectal cancer and their siblings and children. Design: Cost-effectiveness analysis. Data Sources: National colorectal cancer registry data, the Creighton Inter national Hereditary Colorectal Cancer Registry, Medicare claims records, an d published literature. Target Population: Patients with newly diagnosed colorectal cancer and thei r siblings and children. Time Horizon: Lifetime (varies depending on age at screening). Perspective: societal. Interventions: initial office-based screening to determine eligibility (bas ed on personal and family cancer history), followed by tumor testing for mi crosatellite instability, Those with microsatellite instability were offere d genetic testing for HNPCC. Siblings and children of patients with cancer and the HNPCC mutation were offered genetic testing, and those who were fou nd to carry the mutation received lifelong colorectal cancer screening. Measurements: Life-years gained. Results of Base-Case Analysis: When only the patients with cancer were cons idered, cost-effectiveness of screening was $42 210 per life-year gained. W hen patients with cancer and their siblings and children were considered to gether, cost-effectiveness increased to $7556 per life-year gained. Results of Sensitivity Analysis: The model was most sensitive to the estima ted survival gain from screening siblings and children, to the prevalence o f HNPCC mutations among patients with newly diagnosed cancer, and to the di scount rate. In probabilistic analysis, the 90% CI for the cost-effectivene ss of screening patients with cancer plus their relatives was $4874 to $21 576 per life-year gained. Conclusion: Screening patients with newly diagnosed colorectal cancer for H NPCC is cost-effective, especially if the benefits to their immediate relat ives are considered.