Attack of the clones: Unveiling subclonal/heterogenous mismatch repair (MMR)/microsatellite instability (MSI) status in endometrial cancer (EC)

Any time there are two or more tests for a given analyte, there will be some degree of disagreement between them. This editorial contextualizes the recent findings by Riedinger and colleagues regarding discordant mismatch repair and microsatellite instability testing in endometrial cancer.