GENOMIC TESTING FOR
COLORECTAL CANCER
Colorectal cancer is where incomplete molecular testing has the most documented clinical consequences. Partial testing is a real problem -- RAS without NRAS, or RAS and BRAF without MSI, can lead to wrong treatment decisions.
Molecular Biomarkers in Colorectal Cancer
| Biomarker | Frequency | Clinical Implication | When to Test |
|---|---|---|---|
| Extended RAS (KRAS + NRAS) | ~50% of CRC have RAS mutation | RAS mutant: anti-EGFR antibodies contraindicated. RAS wild-type: eligible for cetuximab/panitumumab | Before any anti-EGFR therapy decision |
| BRAF V600E | 8-10% | Encorafenib plus cetuximab approved. BRAF inhibitor alone does not work in CRC | At metastatic diagnosis |
| MSI / MMR status | MSI-H in ~5% of metastatic CRC | Pembrolizumab preferred first-line in MSI-H mCRC. Lynch syndrome implications | At initial CRC diagnosis -- universally |
| HER2 amplification | 2-3% of RAS/BRAF wild-type CRC | T-DXd and tucatinib plus trastuzumab -- emerging options | At metastatic diagnosis |
| KRAS G12C | 3-4% | Sotorasib or adagrasib -- first targetable KRAS mutation | Covered in comprehensive NGS panel |
| NTRK fusions | Rare but pan-cancer | Larotrectinib or entrectinib -- tumour-agnostic approval | Covered in comprehensive NGS panel |
Frequently Asked Questions
How CancerFax Helps
CancerFax is a specialist cancer access and patient-navigation platform. We help patients and families understand their options, organise medical records, coordinate hospital communication, and support cross-border treatment planning where appropriate.
We help collect and organise reports, scans, pathology, biomarker results, and treatment history for structured case review.
We communicate with hospitals or trial teams to assess whether a case may be suitable for further screening.
We support appointment coordination, document submission, translation, and direct communication with international departments.
For international patients, we help with practical coordination — travel planning, hospital admission guidance, and local support.
If this option is not suitable, we help explore other relevant treatments, clinical trials, or advanced care pathways.
From inquiry through to follow-up, our coordinators provide a single point of contact for the family.
CancerFax does not guarantee treatment access, eligibility, or clinical outcome. Our role is to help patients access accurate information, structured review, and appropriate specialist pathways.
Questions About Genomic Testing for Your Colorectal Cancer?
CancerFax reviews your CRC molecular workup to ensure RAS, BRAF, MSI, HER2, and NTRK testing is complete before treatment decisions are made.
This content is for informational purposes only and does not constitute medical advice. Always consult a qualified oncologist before making treatment decisions.