Lifestyle Factors and Microsatellite Instability in Colorectal Cancer: The Evolving Field of Molecular Pathological Epidemiology

Abstract

Colorectal cancer is not a single disease. It encompasses heterogeneous diseases with different sets of genetic and epigenetic alterations. Each tumor arises and behaves in a unique fashion that is unlikely to be exactly recapitulated by any other tumor ( 1 ). Nevertheless, we classify colorectal cancers into a limited number of groups (eg, microsatellite instability [MSI]-high vs microsatellite stability [MSS]) because we assume that tumors with similar characteristics have arisen through common mechanisms and behave in a similar fashion ( 1 ).