Mismatch Repair and Microsatellite Instability Testing for Immune Checkpoint Inhibitor Therapy

Publication Date: August 2, 2022
Last Updated: August 4, 2022

Summary of Recommendations

For patients with CRC being considered for immune checkpoint inhibitor therapy, pathologists should use MMR-IHC and/or MSI by PCR for the detection of DNA MMR defects. Although MMR-IHC or MSI by PCR are preferred, pathologists may use a validated MSI by NGS assay for the detection of DNA MMR defects. (S)
Note: MSI by NGS assay must be validated against MMR-IHC or MSI by PCR and must show equivalency.
324662

Overview

Title

Mismatch Repair and Microsatellite Instability Testing for Immune Checkpoint Inhibitor Therapy

Authoring Organization

College of American Pathologists