The RAS/RAF Panel is an NGS-based assay performed by sequencing the entire coding region (full gene) of BRAF, HRAS, KRAS and NRAS genes. The panel reports mutations detected in the full gene including mutations in the most common hotspots, if present. The common hotspots include KRAS (exons 2-4, including codons 12, 13, 59, 61, 117, and 146), NRAS (exons 2-4, including codons 12, 13, 59, 61, 117, and 146), HRAS (exons 2-3, including codons 12, 13, 59, and 61), and BRAF (exons 11, 15 including codon V600).
KRAS, NRAS, HRAS, and BRAF are members of the RAS/RAF/MAPK pathway. Current guidelines recommend KRAS and NRAS testing in metastatic colorectal cancer for determination of anti-EGFR therapy, and recommend BRAF testing as a marker of poor prognosis. BRAF mutations may predict lack of response to anti-EGFR therapy; evidence is mixed.
- FFPE tissue: Paraffin block is preferred. Alternatively, send 1 H&E slide plus 5-10 unstained slides cut at 5 or more microns. Please use positively-charged slides and 10% NBF fixative. Do not use zinc fixatives.
Use cold pack for transporting block during summer to prevent block from melting. Slides can be packed at room temperature.