Laboratory Test Guide

EGFR Mutations

General Information

Lab Name

EGFR Mutations

Lab Code

EGFRHS

Epic Name

Order using "UW Genetics and Solid Tumor Test Request"


See tip sheet for more information (internal link).

Description

This test detects single-nucleotide and deletion mutations in the EGF receptor (EGFR) gene in exon 18 through exon 21. The detected mutations are the most common acquired mutations in this gene in cancer, and are associated with sensitivity to drugs that inhibit the tyrosine-kinase activity of the EGF receptor protein.

For some lung cancer patients, the mutation status of the EGF receptor gene (EGFR) in their tumor tissue is now being used to choose appropriate therapy. Acquired mutations in exons 18 to 21 of the EGF receptor gene predict response to drugs that inhibit the tyrosine-kinase activity of the EGF receptor protein, such as erlotinib and gefitinib.

References

  • Mok TS, et al. Gefitinib or carboplatin-paclitaxel in pulmonary adenocarcinoma. N Engl J Med 2009, 361:947-57. 19692680
  • Rosell R, et al. Screening for epidermal growth factor receptor mutations in lung cancer. N Engl J Med 2009, 361:958-67. 19692684
  • Sasaki H, et al. EGFR Mutation status in Japanese lung cancer patients: genotyping analysis using LightCycler. Clin Cancer Res 2005, 11:2924-9. 15837743
  • Shigematsu H, et al. Clinical and biological features associated with epidermal growth factor receptor gene mutations in lung cancers. J Natl Cancer Inst 2005, 97:339-46. 15741570

Synonyms

adenocarcinoma, DNA, EGF receptor, epidermal growth factor, erlotinib, gefitinib, lung cancer gene testing, non-small cell, NSCLC, thor, thorplex, tyrosine kinase inhibitors

Components

Code Name
EGFRRE EGFR Result
EGFRCH EGFR Clinical History
EGFRIN EGFR Interpretation
EGFRMT EGFR Method
EGFRDI EGFR Director

Interpretation

Method

Next-generation sequencing. Targeted EFGR exons gene are amplified and hybridized with oligonucleotide probes and sequenced using Next-generation sequencing.

This test was developed and its performance characteristics determined by the Department of Laboratory Medicine at the University of Washington.

Reference Range

See individual components

Guidelines

Ordering & Collection

Specimen Type

Tumor Tissue, Purified DNA, Bone Marrow, Peripheral Blood, accompanied by a PATHOLOGY REPORT for the tested tissue.

Collection

Requirements for Specimen Selection

  • To ensure clinically relevant results, the most recent and/or metastatic sample is preferred to older specimens, provided sufficient tumor is present (see point 2).
  • To ensure detection of all types of mutations there should be at least 10% tumor cells in the tissue area processed for DNA for mutation detection and 20% tumor cells for microsatellite instability evaluation. If there is more than one tissue block, please provide the block that has the greatest percentage of neoplastic nuclei.
  • Tissue samples and pathology reports will be reviewed by directors upon receipt for acceptability prior to testing. Director consultation for tissue selection is available if needed (contact Genetics lab).

Specimen Types

Tissue samples

Send one of the following:

  1. Slides: 1 slide at 4-micron thickness stained with hematoxylin-and-eosin (H&E) AND 10 unstained, non-baked slides at 10-micron thickness (a minimum of 5 unstained slides is acceptable). Unstained slides can be on charged or uncharged slides.
  2. Tissue Blocks: Provide complete formalin-fixed tissue block containing tumor tissue. Tissue block will be returned at completion of testing.
  3. Fresh/frozen tissue: 5 microgram tissue in cell culture medium or frozen tissue stored at -20C. Tumor percentage will not be determined prior to sequencing studies.

NOTE: In order to ensure that enough DNA is obtained, the minimum acceptable tissue area is 10 square millimeters when ten 10-micron slides are supplied (1 cubic millimeter of tissue).

Purified DNA

5 micrograms ANDa reference hematoxylin-and-eosin (H&E) stained slide and pathology report required.

Bone Marrow

1 to 2 mL Bone Marrow in LAVENDER TOP (EDTA) tube

Blood

6 mL blood in LAVENDER TOP (EDTA) tube.

Alternative specimens may be acceptable with approval (contact: 206-598-1149).

For ADD-ON after prior testing, contact Genetics lab.

Unacceptable samples

We cannot accept decalcified samples or tissue samples treated with fixatives other than formalin.

Quantity:

Requested:

  • Tissue: 10 unstained slides (10-micron thickness) plus one H&E-stained slide.
  • Extracted DNA: 5 microgram Bone Marrow: 2 mL
  • Blood: 6 mL

Minimum:

  • Tissue: 5 unstained slides (10-micron thickness) plus one H&E-stained slide.
  • Extracted DNA: 100-250 nanograms Bone Marrow: 1 mL
  • Blood: 3 mL

Forms & Requisitions

Genetics Requisition

Providers with access to the UW implementation of Epic (i.e., FHCC, HMC, SCCA, UWMC, UWNW) may order this test using the order "UW Genetics and Solid Tumor Test Request." See tip sheet for more information (internal link).

Handling Instructions

Please attach a copy of the pathology report for the tumor sample being submitted.

Hold slides or tissue blocks at room temperature.

Outside Laboratories: Ship at room temperature.

Stability: unstained slides or tissue blocks stable at room temperature for at least 2 years.

Quantity

requested: Tissue: 10 unstained slides (10-micron thickness) plus one H&E-stained slide. Extracted DNA: 5 microgram Bone Marrow: 2 mL Blood: 6 mL
minimum: Tissue: 5 unstained slides (10-micron thickness) plus one H&E-stained slide. Extracted DNA: 100-250 nanograms Bone Marrow: 1 mL Blood: 3 mL

Processing

Hold slides or tissue blocks at room temperature.

Outside Laboratory: Ship at room temperature.

Stability: unstained slides or tissue blocks stable at room temperature for at least 2 years

Performance

LIS Dept Code

Genetics (GEN)

Performing Location(s)

UW-MT Genetics

Attention: Genetics Lab
Clinical lab, Room NW220
University of Washington Medical Center
1959 NE Pacific Street
Seattle, WA 98195

Tel: 206-598–6429 M–F (7:30 AM–4:00 PM)
Fax: 206-616-4584
Lab email: cgateam@uw.edu

Tel (EXOME only): 206-543-0459

Faculty
Jillian Buchan, PhD, FACMG
Runjun Kumar, MD, PhD
Regina Kwon, MD, MPH
Christina Lockwood, PhD, DABCC, DABMGG
Abbye McEwen, MD, PhD
Colin Pritchard, MD, PhD
Vera Paulson, MD, PhD
Eric Konnick, MD, MS
He Fang, PhD

Frequency

Run at least once a week; Typical Turnaround: 2 weeks *Turn around times may vary based on factors such as tissue acquisition and insurance preauthorization.

Available STAT?

No

Billing & Coding

CPT codes

81235, 81479

Billing Comments

For pricing information, contact Client Support Services 206-520-4600 or 800-713-5198.

LOINC

21666-3