Testing tumours for mismatch-repair deficiency and microsatellite instability to inform immunotherapy and screening.
Standards for testing mismatch-repair (MMR) and microsatellite instability (MSI) status.
A guideline from the College of American Pathologists (CAP), developed with the Association for Molecular Pathology (AMP) and partners, on testing tumours for mismatch-repair (MMR) deficiency and microsatellite instability (MSI).
MMR / MSI status can indicate whether a tumour may respond to immune checkpoint inhibitor (immunotherapy) treatment, and can flag cases that warrant screening for Lynch syndrome. It is most established in colorectal and endometrial cancers but is relevant across tumour types.
When MMR / MSI testing is requested, our reporting reflects these principles so results are clear for both treatment and screening decisions.
Tell us what you need, our team will help with sample requirements, turnaround, and reporting.