Mismatch repair deficiency: a step forward personalized medicine in endometrial cancer?

Abstract

Endometrial cancer (EC) is the most common female malignancy in the world, it has traditionally been classified into two subgroups based on histopathological features, however this dualistic classification does not take into consideration subtypes such as high-grade endometrioid EC. Recently, work performed as part of The Cancer Genome Atlas study has focused on molecular genomic classification of EC, with four distinct molecular subtypes described: 1. POLE ultramutated, associated with a good prognosis; 2. Microsatellite instability (MSI) hypermutated; 3. Copy number low and microsatellite stable; 4. Copy number high, serous like, associated with a poor prognosis. The subgroup of patients with MSI is of particular interest for a number of reasons, including the use of tumour screening to identify patients with Lynch syndrome, the prognostic significance of MSI, and the potential therapeutic implications. This review will focus on the current knowledge in these areas and potential future directions.