BRAF Mutation Analysis with Interpretation

Label Mnemonic:	BRAF
Epic code:	LAB1588
Downtime form:	Doctor/Provider Orders - Pathology Molecular

Molecular Pathology
6240 RCP
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