Dr. Strickler on the Importance of Molecular Markers in mCRC

John Strickler, MD, assistant professor of medicine, Duke University School of Medicine, gastrointestinal oncologist, Duke Cancer Institute, discusses improvements in the treatment of metastatic colorectal cancer (mCRC).

It is an exciting time for clinical development in mCRC and gastrointestinal malignancies in general, Strickler says. There have been incremental improvements in survival with new therapies, as well as new strategies for selection. One of these strategies is cell-free DNA (cfDNA), also known as liquid biopsy, which is being used to aid in understanding the genomic drivers of acquired resistance. cfDNA has been useful thus far in the treatment of patients with mCRC, as it can identify markers that inform treatment decisions.

The paradigm is shifting, Strickler says, particularly with the use of microsatellite instability (MSI) as a tool to select patients for immunotherapy. For example, patients with mCRC who are microsatellite instability-high can receive pembrolizumab (Keytruda). There are also patients with rare alterations that are highly actionable. These patients can experience exceptional benefit if these alterations are identified and targeted, Strickler says.