Microsatellite instability-high solid malignant tumor

A microsatellite instability-high solid malignant tumor is a cancer of non-hematologic origin defined by significant genomic hypermutability within short, repetitive DNA sequences known as microsatellites

A microsatellite instability-high solid malignant tumor is a cancer of non-hematologic origin defined by significant genomic hypermutability within short, repetitive DNA sequences known as microsatellites

This biomarker-driven condition arises from defective cellular DNA mismatch repair (dMMR), caused either by sporadic epigenetic silencing (such as MLH1 promoter hypermethylation) or inherited germline variants associated with Lynch syndrome The phenotype occurs across diverse anatomical sites—most commonly in gastrointestinal and endometrial tissues—and affects both adult and pediatric populations with localized or metastatic disease

This biomarker-driven condition arises from defective cellular DNA mismatch repair (dMMR), caused either by sporadic epigenetic silencing (such as MLH1 promoter hypermethylation) or inherited germline variants associated with Lynch syndrome Pathophysiologically, the failure to repair replication errors produces a markedly elevated tumor mutational burden and an abundance of frameshift-derived neoantigens, which typically elicit dense intratumoral immune infiltration

This biomarker-driven condition arises from defective cellular DNA mismatch repair (dMMR), caused either by sporadic epigenetic silencing (such as MLH1 promoter hypermethylation) or inherited germline variants associated with Lynch syndrome Pathophysiologically, the failure to repair replication errors produces a markedly elevated tumor mutational burden and an abundance of frameshift-derived neoantigens, which typically elicit dense intratumoral immune infiltration

The phenotype occurs across diverse anatomical sites—most commonly in gastrointestinal and endometrial tissues—and affects both adult and pediatric populations with localized or metastatic disease

The phenotype occurs across diverse anatomical sites—most commonly in gastrointestinal and endometrial tissues—and affects both adult and pediatric populations with localized or metastatic disease