General treatment for metastatic colorectal cancer: From KEYNOTE 177 study.

In the palliative treatment of metastatic colorectal cancer (mCRC), doublet chemotherapy (FOLFOX or FOLFIRI) or triplet chemotherapy (FOLFOXIRI) combined with targeted drugs (cetuximab or bevacizumab) is the main regimen. Recently, microsatellite instability-high (MSI-H) or DNA mismatch repair deficient (dMMR) was discovered as a biomarker to distinguish immunotherapy-benefited populations. In this context, recently published randomized phase III clinical trials tested the efficacy and safety of immunotherapy and traditional chemotherapy with or without targeted drugs as first-line treatment for patients with MSI-H/dMMR mCRC. Here, we briefly analyze this article and further discuss immune monotherapy or double immunotherapy for patients with MSI-H/dMMR mCRC, the immunotherapy for patients with BRAF V600E mutant mCRC, and the immunotherapy for patients with microsatellite stable mCRC.