Revised Bethesda Guidelines vs. MSI Testing for the Detection of HNPCC Mutations

Identification of hereditary nonpolyposis colorectal cancer (HNPCC) gene carriers is currently suboptimal, even in cancer patients and their family members. The Amsterdam criteria lack sensitivity for identifying people who carry genetic mutations, and the Bethesda guidelines — which were developed to preselect patients for microsatellite instability (MSI) testing before germline mutation screening — have produced mixed results. The Bethesda guidelines were recently revised to improve the detection of HNPCC in patients with late onset or no family histories of disease (J Natl Cancer Inst 2004; 96:261). Now, researchers have compared the performance of MSI testing based on the revised Bethesda guidelines with that of universal MSI tumor test…