Scroll Back to Top

NRAS Gene Mutation Analysis, Extended

CPT To be determined. Updates will be made when available.

Test Details

Turnaround Time

5 - 7 days

Use

NRAS is a guanosine triphosphate (GTP)-binding protein involved in downstream receptor signaling, which is critical for cell proliferation, survival and differentiation. Mutations in the NRAS oncogene are frequently found in human cancers. They are common in melanomas, colorectal cancer and thyroid cancer. This assay detects NRAS mutations in exons 2, 3 and 4, allowing the determination of drug response.

Special Instructions

Provide a copy of the pathology report; the NRAS test will be delayed if the pathology report is not received. Direct any questions regarding this test to customer service at 800-345-4363.

Limitations

This assay is able to detect 5% mutation in a background of wild-type DNA. 

This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration.

Methodology

SNaPshot Multiplex PCR (primer extension-based method)

References

Bae JS, Choi SK, Jeon S, et al. Impact of NRAS mutations on the diagnosis of follicular neoplasm of thyroid. Int J Endocrinol. 2014:289834. PubMed 25254041
Benson AB 3rd, Bekaii-Saab T Chan E, et al. Rectal cancer. J Natl Compr Canc Netw. 2012 Dec 1;10(12):1528-1564. PubMed 23221790
Benson AB 3rd, Venook AP, Bekaii-Saab T, et al. Colon cancer, version 3.2014. J Natl Compr Canc Netw. 2014 Jul;12(7):1028-1059. PubMed 24994923
Bokemeyer C, Van Cutsem E, Rougier P, et al. Addition of cetuximab to chemotherapy as first-line treatment for KRAS wild-type metastatic colorectal cancer. Pooled analysis of the CRYSTAL and OPUS randomized clinical trials. Eur J Cancer. 2012 Jul; 48(10):1466-1475. PubMed 22446022
Douillard JY, Siena S, Cassidy J, et al. Randomized, phase III trial of panitumumab with fluorouracil, leucovorin, and oxaliplatin (FOLFOX4) versus FOLFOX4 alone as first-line treatment in patients with previously untreated metastatic colorectal cancer: The PRIME study. J Clin Oncol. 2010 Nov 1;28(31):4697-4705. PubMed 20921465
Thumar J, Shahbazian D, Aziz SA, Jilaveanu LB, Kluger HM. MEK targeting in N-RAS mutated metastatic melanoma. Mol Cancer. 2014 Mar 4;13:45-54. PubMed 24588908

Specimen Requirements

Information on collection, storage, and volume

Specimen

Formalin-fixed, paraffin-embedded (FFPE) tissue or slides

Volume

Formalin-fixed, paraffin-embedded tissue block or four unstained slides and one matching H&E-stained slide at 5 μM

Minimum Volume

Two unstained slides and one matching H&E-stained slide at 5 μM; samples with >4mm² and ≥50% tumor content are preferred

Container

Formalin-fixed, paraffin-embedded (FFPE) tissue blocks or slides

Storage Instructions

Maintain blocks/slides at room temperature.

Causes for Rejection

Tumor block containing insufficient tumor tissue; broken or stained slides