Bowel cancer isn’t just one thing. There are lots of bowel cancers.
Some of the differences between bowel cancers are due to types genetic mutations in the cell, some of the differences are due to the person’s own genetic make-up. Biomarkers help to identify these differences.
- Biomarkers are molecules that can be found in your body tissues, blood, or tumours.
- Biomarkers can indicate that normal cell processes are not working correctly.
- Biomarkers can be used to target treatment to make it more effective.
At present the most important biomarkers for bowel cancer are
- KRAS
- NRAS
- BRAF
- HER2
In the UK patient biopsies and tumours are typically tested for the KRAS, NRAS and BRAF biomarkers. If have a bowel cancer diagnosis you may find that these terms are mentioned, along with MSI – Microsatellite Instability.
Full details of which biomarker tests should be carried out are available on the NHS website
National Genomic Test Directory
The presence of particular versions of biomarkers may indicate that the standard forms of chemotherapy may be ineffective for advanced cancer, and it may be more appropriate to use a targeted therapy including immunotherapy. Visit the Cancer Research UK page on targeted therapy
The Global Colon Cancer Association has a guide to biomarkers:
An important ‘family’ of biomarkers are known as KRAS.
KRAS Kickers is a US based group that provides detailed information about these biomarkers