High-Frequency Microsatellite Instability

**Semantic type:** Cell or Molecular Dysfunction

**Definition:** The presence of genomic instability associated with defective DNA mismatch repair in greater than 30% of the microsatellite instability (MSI) biomarkers in a tumor sample.

**Synonyms:** - High - MSI high - MSI-H - Microsatellite Instability High - Microsatellite Instability-High