Colorectal Cancer : NRAS Variant Analysis

Test Information

KRAS: Mutations in exon 2 of KRAS are reported in 40% of CRC with codon 12 and 13 identified as the two hotspots accounting for about 95% of all mutation types. These presence of these mutations predict a lack of response to EGFR inhibitors cetuximab and panitumumab therapies (The Lancet Oncology (2014) 15(10): 1065-75; New England Journal of Medicine (2013) 369(11) 1023-34). Based on the clinically available information, the National Comprehensive Cancer Network (NCCN) recommends all patients with metastatic colorectal cancer have KRAS/NRAS genotyping and, if positive, to not be treated with EGFR inhibitors (cetuximab or panitumumab).

Turnaround Time

5 days

CPT Code(s)






Gene sequencing and targeted mutation testing and copy number analysis can serve as a useful diagnostic and potentially prognostic tool for the analysis of affected tissues or tumors. The detection of copy number variants or specific gene mutations may enhance treatment decisions.

Specimen Requirements

Analysis can be performed on fresh or frozen tissue samples as well as formalin-fixed, paraffin-embedded tissue samples.

Transport Instructions

The specimen should be kept at the appropriate temperature and delivered via overnight shipping.

Have Questions Need Support?

Call our laboratory at 1-800-473-9411 or contact one of our Laboratory Genetic Counselors for assistance.
Robin Fletcher, MS, CGC
Kellie Walden, MS, CGC

Oncology Testing, Targeted Variants
Lucy's Story

Lucy's Story

When our daughter Lucy had a metabolic crisis at 7 days old, we were shocked and devastated to find out that she was born with a rare genetic disorder (MSUD). Her newborn screening results did not make it back in time to prevent the crisis, and no one at our local hospital was familiar with the disease. They did not know how to treat her. Calls were made to Greenwood Genetic Center to confirm her diagnosis...

In The News