What is your approach for perioperative chemotherapy in MSI-H/dMMR localized gastric cancer?

This question gets at aspects of MSI-H biology, biomarker testing and post-hoc data from the MAGIC and CLASSIC trials suggesting a lack of benefit, and potential negative impact of treatment in MSI-H patients. The following is restricted to gastric cancer, and the rates of MSI-H in true esophageal a...

As ever, @Dr. First Last provides an exhaustive analysis of this topic and has the receipts/references to back it up.

I would approach this answer with a slightly different emphasis. Firstly, in addition to the references he cites, there is the individual patient data meta-analysis by Pietrantonio an...