High predictability for identifying Lynch syndrome via microsatellite instability testing or immunohistochemistry in all Lynch-associated tumor types.

Abstract

Lynch syndrome is an inherited cancer-prone syndrome identified in ~3% of all colorectal cancer (CRC) patients and ~2% of all endometrial cancer (EC) patients (1-3). It is defined by identification of a germline mutation in one of the DNA mismatch repair (MMR) genes ( MSH2, MLH1, MSH6, PMS2, EPCAM ) whose proteins function to maintain replication fidelity of DNA prior to mitosis, and sets it apart from other hereditary non-polyposis colorectal cancer (HNPCC) syndromes such as Familial Colorectal Cancer Type X and Polymerase Proofreading Polyposis syndrome (3).