Physicians also need to consider the influence of specific mutations and molecular alterations on the course of CRC. For example, BRAF mutations, which are found in up to 15% of sporadic colorectal cancer cases, are associated with a poor prognosis. In contrast, patients with a high degree of microsatellite instability (MSI-H) often have a more favorable prognosis.

Importantly, multiple mutations may exist in a single tumor. In one study of 2,686 patients with stage III colon cancer, approximately 50% of patients with MSI-H tumors also had BRAF mutations. In these patients, MSI-H status was not associated with improved survival.