Dr. Duval on the Use of MSI-H as a Biomarker of Response in Patients With Cancer

Alex Duval, MD, PhD, professor of molecular oncology, director, Instability of Microsatellites and Cancer team, Saint-Antoine Research Center, French Institute of Health and Medical Research, discusses the use of microsatellite instability–high (MSI-H) as a biomarker of response to therapy in patients with cancer.

​As a biomarker of response, MSI-H can influence ​and guide clinical treatment decisions, says Duval. Moreover, MSI status may be the first indication that giving immunotherapy with checkpoint inhibitors is warranted in a particular patient.

Currently, using MSI status to inform immunotherapy initiation is commonly used in the metastatic setting. However, this concept will likely be applied to the non-metastatic to inform response other drugs such as chemotherapy.

Notably, this applies to a host of therapies, including chemotherapy. For example, it is now understood that patients ​with gastric cancer who are MSI-H will not ​respond to chemotherapy, Duval concludes.