Test Code KRASO K-RAS Mutation Assay
Specimen Type
Block, paraffin embedded tissue or frozen sections
Container/Tube
Block or slides
Offsite Collection Instructions
Slides/blocks labeled with two patient identifiers and a
surgical pathology ID.
Turnaround Time
8-10 business days
Test Includes
This is no longer a Molecular Diagnostics standalone test!
This is a next-generation sequencing assay for detection of
somatic mutations located within mutational hotspot regions of
the
KRAS gene,
exons 2, 3 and
4.
Preferred Volume
n/a
UCMC Collection Instructions
Formalin fixed tissue (paraffin block, unstained slides).
Test Usage
KRAS
mutations frequently found in
neoplasms include those at exon 2 (codons 12 and 13) and exon 3
(codon 61). Mutations in KRAS codons 12
and 13 have been associated with lack of response to EGFR-targeted therapies in
both CRC
(colorectal cancer) and NSCLC
(non-small-cell lung cancer)
patients.
Critical Results
None
Test Limitations
- This test will not detect mutations in areas outside the
targeted genomic regions. - Copy number alterations and translocations will not be
detected. - This test is not intended to detect minimal residual
disease. - Assay sensitivity is 5% mutant allele frequency, thus
false-negative results may occur when there is a lower mutant
allele burden. - Variants present at oligonucleotide binding sites may
negatively interfere with hybridization (as with any PCR-based assay),
potentially resulting in allelic
under-sampling or drop-out.
Additional Information
Reporting: Mutations with known or possible pathogenic or
clinical significance are reported. Variants of unknown
significance are reported as such.
Fee Code
79812
Synonyms
KRAS;
K-RAS;
k-RAS
DAY(S) AND TIME(S) PERFORMED
Monday -Friday, 9AM – 5PM
STAT DAY(S) AND TIME(S) PERFORMED
Not Available
CPT
81275
Method Name
KRAS gene is
part of the OncoScreen
ST2.0 NGS
panel. The OncoScreen procedure
is performed and data for KRAS gene only
is analyzed.
The OncoScreen test is based on the Ion AmpliSeq Cancer
Hotspot
Panel (IACHP)
v2 (Life Technologies).
After DNA is
isolated and its quality and
quantity determined, a single multiplexed PCR is performed using a
single reaction containing
the 207 Ion AmpliSeq Cancer Hotspot primer pairs. It is then
cleaned up using Ampure XP beads and a library is constructed
using
KAPA
HTP
Library Preparation Kit and Illumina compatible adapters.
Through
the library construction, adapter oligonucleotides containing
unique patient-specific “barcode” indexes and P5/P7
sequences are ligated onto the amplicon PCR products to make an
Illumina compatible
sequencing library.All DNA samples for
a
given run are processed in duplicate and in parallel, and then
following a library quantitation, samples with different
bar-code
sequences are pooled and sequenced in a 2 × 152 bp MiSeq
run.
Reference Values
Interpretative report will be provided.