Gene and marker tests
MSI-H (microsatellite instability high)
Also written as MSI-H, MSI high, Microsatellite instability, MSI, MSS, Microsatellite stable
What it means
Microsatellite instability is a change in cells in which the number of repeated DNA bases in a short repeated stretch of DNA is different from what was inherited. It can come from mistakes that are not corrected when DNA is copied. It is found most often in colorectal, stomach and womb-lining cancers.
Why it matters
Knowing whether a cancer has microsatellite instability may help plan the best treatment. Your oncologist decides.
Ask your oncologist
"Was my tumour tested for MSI, and what did it show?"
From NCI Dictionary of Cancer Terms: microsatellite instability. Not medical advice: your oncologist decides.