Is my tumor MSI-High or MSS, and how does this affect treatment
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For informational purposes only
This answer was generated by AI grounded in NCCN guidelines and published medical literature. It is not medical advice. Always consult your oncologist or care team before making treatment decisions.
To answer your question, I would need:
- Your pathology report or tumor testing results
- Any molecular testing reports (like immunohistochemistry, PCR, or sequencing results)
- Lab reports that specifically mention "MSI" (microsatellite instability) status
Once you share those documents, I can explain:
- Whether your results show MSI-High or MSS (microsatellite stable)
- What that finding means in plain language
- How it typically influences colorectal cancer treatment decisions
Quick Educational Context (While You Gather Records):
MSI Status Basics: According to CancerPatientLab educational resources, microsatellite instability (MSI) refers to errors in your tumor's DNA that aren't being corrected properly. Think of it like a typewriter without spell-check—mistakes accumulate and aren't fixed.
- MSI-High tumors typically respond well to immunotherapy drugs (like pembrolizumab/Keytruda)
- MSS tumors usually follow different treatment pathways
This distinction is important because it's one of the first "tissue-agnostic" biomarkers approved by the FDA—meaning the treatment recommendation is based on what the tumor is made of, not just where it started in your body.
Please upload your test results, and I'll provide a detailed educational interpretation.
This information is for educational purposes only. Always consult your healthcare team for personalized medical advice and decisions.
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NCCN Guidelines for Patients: Colon Cancer (2026)Browse all NCCN Guidelines for Patients →Related Services
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