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Intermediate Technical IVT

TMB-high

A tumor classification indicating high mutation burden that predicts response to immune checkpoint inhibitors.

Full Definition

TMB-high (tumor mutational burden-high) is a biomarker classification indicating that a tumor contains an elevated number of somatic mutations, typically defined as ≥10 mutations per megabase. High mutation burden is associated with increased neoantigen production, making tumors more likely to respond to immune checkpoint inhibitors. This biomarker has gained regulatory approval as a tumor-agnostic indication for pembrolizumab treatment. TMB-high status can occur across various cancer types and may be detected through comprehensive genomic profiling. The threshold for defining TMB-high may vary depending on the assay platform and specific clinical context.

Usage

Usage note: Always hyphenate; specify threshold value and assay platform when reporting

In Context

  • "The patient's colorectal cancer was classified as TMB-high, making them eligible for immunotherapy." — Treatment planning documentation
  • "TMB-high status was confirmed using a validated next-generation sequencing assay." — Molecular pathology report

Also known as

high tumor mutational burden TMB-H

Contrasted with

TMB-low microsatellite stable

Don't confuse with

MSI-high high-grade PD-L1 high

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