Colorectal Cancer

Predictive testing

Testing in the context of metastatic colorectal cancer is available using our Oncopanel multigene NGS panel.

The Oncopanel assay can detect mutations in a variety of predictive and prognostic genes including KRAS, NRAS and BRAF, as well as in genes associated with inherited cancer predisposition.

Lynch syndrome


Lynch syndrome is an inherited predisposition to the development of cancer (primarily colorectal and endometrial cancer) that is associated with defects in DNA mismatch repair (MMR) genes, most commonly MLH1, PMS2, MSH2 and MSH6. Immunohistochemistry (IHC) based screening for loss of these proteins within the tumour can help identify patients that may benefit from diagnostic (germline) testing.

  • MMR screening by IHC is offered by BC Cancer Anatomic Pathology (see the BC Cancer Laboratory Services website for details)
  • Microsatellite instability (MSI) testing is available but not routinely offered by our laboratory in the context of MMR deficient tumours, since MMR IHC screening is a suitably specific alternative. As IHC is incompletely sensitive toward Lynch Syndrome proper, should a patient’s family history be suggestive of Lynch Syndrome, a referral to the Hereditary Cancer Program is recommended. MSI testing may also be of benefit in cases where IHC results are not clearly informative. Please contact the laboratory to discuss cases where MSI testing may be appropriate.
  • For specimens displaying both MLH1- and PMS2-deficiency by IHC, reflex BRAF V600 genetic testing is available to help differentiate patients with sporadic cancers from those that may benefit from germline testing.  An existing BRAF V600E positive or negative result by IHC is suitable for this assessment and these specimens do not require a confirmatory BRAF V600 genetic test.

NOTE: The results of these screening tests are not a substitute for germline testing.  If a patient has clinical features or a personal or family history suggestive of an inherited syndrome then a Hereditary Cancer referral should be made regardless of results. 

Diagnostic Testing

Diagnostic testing for Lynch Syndrome is available for BC Patients through a referral to the Hereditary Cancer Program at BC Cancer (see our Hereditary Cancer page for details).