Dr. Kopetz on the Importance of Molecular Testing in CRC

Scott Kopetz, MD, PhD, FACP, associate professor, Department of Gastrointestinal Medical Oncology, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center, discusses the importance of molecular testing in colorectal cancer (CRC).

The current guidelines suggest that microsatellite instability (MSI) testing should be done in every patient with CRC regardless of stage, Kopetz says. MSI testing is often done by immunohistochemistry, but it can also be done by a polymerase chain reaction test. This has important implications for family members, as MSI status can signal a hereditary risk for CRC. Additionally, it can inform treatment decisions for immunotherapy.

Kopetz says that other tests that should be done are KRAS, NRAS, and BRAF testing—which are all considered standard. HER2 gene amplification testing is starting to be done in some institutions, as HER2 status can provide predictive and prognostic information. Kopetz predicts that HER2 gene amplification testing will become a part of the guidelines in the near future.