Only <5% of metastatic colorectal cancer is mismatch repair deficient (dMMR) or microsatellite instability-High (MSI-H). However, it is such an important predictive biomarker for quick, sometimes dramatic, and durable response to immunotherapy as seen in the first line studies (CheckMate 142, KEY...

The question posed “Would you give adjuvant pembrolizumab in a MSI-H oligometastatic colorectal cancer status-post resection that responded to neoadjuvant ICI? is incomplete:   What kind of resection was it? Was it a resection of primary plus oligometastatic sites? Or was there a prior r...