BRAF Mutation Analysis with Interpretation
Label Mnemonic: BRAF
Epic Lab Code: LAB1588
Downtime Form: A-1a Molecular Pathology/Diagnostics Laboratory Requisition
Molecular Pathology
6004 BT GH
384-9568
Specimen(s):
Formalin fixed, paraffin embedded tissue block or 10 unstained 5-10 μM slides at 20-25°C and an H&E slide of the tissue
Minimum:
Tumor cells more than 50% of the total tissue and greater than 10mm2 in surface area on the block.
Rejection Criteria:
Specimens fixed in B5 fixative or that have been decalcified will not be accepted. Tumor specimens containing less than 50% tumor cells or are less than 10mm2 in area may be unacceptable.
Testing Schedule:
Weekly
Turn Around Time:
7-10 working days
Reference Range:
Negative
Comments:
BRAF mutations have been described in primary and metastatic melanoma (30-70%), papillary thyroid carcinoma (40-70%), colorectal (5-20%), ovarian (5-10%) and prostate (5-10%) adenocarcinomas, testicular cancer (25%), cholangiocarcinoma (10-20%), and less frequently in a variety of other neoplasms including non-small cell lung cancer and squamous carcinoma of the head and neck. Most BRAF mutations occur at position c.1799T>A, encoding a missense p.V600E that results in increased kinase activity and signal transduction through the MAP kinase pathway.

The presence of BRAF p.V600 activating mutations is generally considered to be a poor prognostic marker in metastatic colorectal cancer, may decrease or abolish the efficacy of therapeutic agents targeting tyrosine kinases proximal to BRAF signaling, and correlates with increased sensitivity to selective BRAF mutant inhibitors.
Methodology:
Polymerase Chain Reaction (PCR) followed by Sequencing
CPT Code:
81210