RAS Mutation Detection in Tumors
Sequencing
Indication
To detect activating point mutations in the KRAS and NRAS genes, which are commonly present in leukemias with monocytic differentiation (AML, CMML), and in solid tumors such as melanoma, lung cancer and colorectal carcinoma. Presence of KRAS mutations have been shown to confer resistance to anti-EGFR monoclonal antibodies.
Methodology
PCR-based DNA sequencing; this assay also available on Next Gen Sequencing platforms (CMS46 and CMS53).
Test Parameters
The presence of mutations in codons 12 and 13 as well as codon 61 of NRAS and KRAS are assessed in four separate PCR-DNA sequencing reactions.
Sensitivity
The sensitivity of detection is approximately one mutated cell per five total cells in sample (20%).
Turnaround Time
10-14 working days
Sample Requirements
- 10-30 ml peripheral blood in lavender top (EDTA) tube, sent on wet ice
or - 2-3 ml bone marrow aspirate in EDTA, sent on wet ice
or - 20 µg of purified DNA, sent on dry ice
Formalin-fixed, paraffin embedded tissue blocks containing adequate amounts of tumor to be analyzed (See Sensitivity.)
Please provide a copy of the corresponding pathology report.
CPT Codes
81275, 81403, 81404
Additional charges may apply for tissue extraction.
The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.