Dr. Chalabi on the Role of MSI Testing in CRC

Myriam Chalabi, MD, a medical oncologist at the Netherlands Cancer Institute, discusses the utility of microsatellite instability (MSI) testing in colorectal cancer (CRC).

MSI testing is widely utilized for patients with CRC, says Chalabi. It’s critical to understand MSI test results because they can help guide treatment selection, especially amid the rise of several effective immunotherapy options. Notably, MSI testing results can be particularly beneficial for patients with metastatic CRC, larger tumors, or those who need induction therapy prior to undergoing surgery. Patients at the Netherlands Cancer Institute are typically recommended for clinical trials that are evaluating the role of neoadjuvant immunotherapy, such as the NICHE trial (NCT03026140), Chalabi says. 

The NICHE trial is currently recruiting and is the first neoadjuvant trial to evaluate the role of ipilimumab (Yervoy) in combination with nivolumab (Opdivo) in patients with early-stage CRC. Patients globally are recommended for this study, says Chalabi. Moreover, based on initial findings from the NICHE trial, ipilimumab/nivolumab may be preferrable to chemotherapy, which is the standard of care in this setting in several parts of the world, Chalabi explains. In the United States, immunotherapy is the standard for patients with MSI tumors and metastatic disease; however, in the Netherlands, patients must be enrolled in a clinical trial, Chalabi concludes.