KRAS Mutations: Codons 12, 13 and 61

Specimen Collection, Storage, and Shipping

Test Information:

Activating somatic mutations of KRAS are present in approximately 20-30% of human malignancies, including 30-50% of colorectal cancers and 30% of adenocarcinomas of the lung. The mutation status of KRAS and other oncogenic drivers, combined with clinical features, help guide tumor therapy. This pyrosequencing assay is designed to detect as low as 5% mutation frequency in codons 12 and 13 in exon 2 and codon 61 in exon 3. Generally, this would represent a minimum requirement of 10% tumor nuclei out of total nuclei within an anatomic pathology specimen.

Requisition Code:
KRAS mutations (codons 12, 13, and 61)

CPT Codes:
81275; 81276; G0452-26 (x2) (add G88381 if manual dissection is needed)

Turn Around Time:
7-10 days

Specimen Requirements
Decalcified specimens are not accepted

Paraffin Block

Collect: Formalin-fixed, paraffin embedded tissues

Storage: Room temperature

Remarks: Submit the paraffin block, 1 H&E with marked location of most abundant tumor (or photocopy of marked H&E) and an approximate % of tumor cells in the area and a copy of the Surgical Pathology report.

Transport: See Standard Shipping Procedures

References:

  1. Sepulveda AR, Hamilton SR, Allegra CJ, et al. Molecular Biomarkers for the Evaluation of Colorectal Cancer: Guideline from ASCO, CAP, AMP, ASCO. J Mol Diagn. 2017 Mar;19(2):187-225. doi: 10.1016/j.jmoldx.2016.11.001. Epub 2017 Feb 6.
  2. Lindeman NI, Cagle PT, Aisner DL, et al. Updated Molecular Testing Guideline for the Selection of Lung Cancer Patients for Treatment with Targeted Tyrosine Kinase Inhibitors: Guideline from CAP, IASLC, AMP. J Mol Diagn. 2018 Mar;20(2):129-159. doi: 10.1016/j.jmoldx.2017.11.004. Epub 2018 Jan 23.