Immunotherapy is an established treatment option for dMMR/MSI-H metastatic colorectal cancer (mCRC) but its optimal duration remains to be determined. A fixed duration of 2 years or until progression or toxicity has been adopted based on the KEYNOTE-177 study. More recently, the GERCOR NIPICOL phase...

There is limited prospective evidence that I am aware of to guide management in this situation. If the patient is responding to and tolerating immunotherapy for unresectable dMMR colon cancer, then I would likely continue therapy until either 1) completion of two years of therapy (as per KN-177), 2)...