FoundationOne® CDx
Comprehensive Profiling
DNA, RNA, and Genomic Signatures

Calling FoundationOne® CDx a "324-gene panel" is technically correct—but it misses the structure of the assay.
Foundation Medicine's FoundationOne CDx evaluates multiple layers of genomic information, combining DNA alterations, RNA fusion rearrangements, and genomic signatures to support therapy selection across oncology.
What the Test Measures
DNA Alterations
- 324 genes evaluated
- Detects mutations, insertions/deletions (indels), and copy number alterations
- Includes key oncogenic drivers such as EGFR, KRAS, BRAF, BRCA1/2, and others
RNA Fusion Rearrangements
- Detection of clinically relevant gene fusions
- Includes drivers such as ALK, ROS1, NTRK, RET, and others
Genomic Signatures
- MSI (Microsatellite Instability)
- TMB (Tumor Mutational Burden)
Why This Matters
These biomarkers collectively support approximately 175 FDA-approved therapy–biomarker combinations across oncology indications.
Understanding the structure of the assay is critical for appropriate test selection and interpretation—particularly as treatment decisions become increasingly biomarker-driven.
How Casandra Structures This
At Casandra.ai, we break diagnostic tests down into their underlying components—biomarkers, measurement types, specimen requirements, and clinical context.
This allows providers to understand not just what a test is called, but what it actually measures—and how it fits into clinical decision-making.
