Microsatellite Instability Is Insufficiently Used as a Biomarker for Lynch Syndrome Testing in Clinical Practice

Abstract

Although MSI analysis is routinely performed in clinical practice, as many as 77% of MSI-high patients do not undergo LS genetic testing, despite international guidelines strongly recommending it. <i>BRAF</i> and <i>MLH1</i> methylation analysis could shed light on the somatic origin of MSI in 42.50% of the MSI-high patients; however, <i>MLH1</i> analysis is barely ever requested in clinical practice.