
Tumor mutation burden (TMB) and colorectal cancer.


What is tumor mutation burden (TMB)?
Tumor mutation burden (TMB) is a measure of the number of mutations carried by tumor cells. Tumors with many mutations have a high mutation burden (high TMB).
Many tumors with a high TMB (equal to or greater than 10) also have the biomarker MSI-H.
In MSI-H tumors, the somatic mutation occurs in one of the DNA mismatch repair genes that also results in MSI-H. These mutations can be passed along to new tumor cells during cell division. A small percentage of tumors with TMB also have the biomarker MSS.

What happens if I have a high TMB?
Knowing the TMB score of a tumor may help predict how well it will respond to immunotherapies.
This can help you and your doctor find the right treatment plan for you.
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