Scroll Back to Top

EGFR Mutation Analysis

CPT 81235; 88381
Synonyms
  • Erlotinib Responsiveness in NSCLC, EGFR Mutation Analysis
  • Gefitinib Responsiveness in NSCLC, EGFR Mutation Analysis
  • IRESSA® Responsiveness in NSCLC, EGFR Mutation Analysis
  • Non−Small-cell Lung Cancer, EGFR Mutation
  • Tarceva® Responsiveness in NSCLC, EGFR Mutation Analysis

Test Details

Cancer Type

Lung, Non-small cell lung cancer

Technology Used

Molecular

Turnaround Time

5 - 7 days

Use

In non-small cell lung cancer, many mutations in EGFR are associated with responsiveness to EGFR tyrosine kinase inhibitor (TKI) therapy. In contrast, some mutations in EGFR are associated with resistance to EGFR TKI therapy, including T790M and EGFR exon 20 insertions. The T790M mutation is a known mechanism of resistance and is commonly associated with relapse following initial therapy with EGFR TKI.

Special Instructions

Please provide a copy of the pathology report. Please direct any questions regarding this test to customer service at 800-345-4363. A subsequent blood sample may be requested in order to confirm the somatic origin of an identified mutation.

Limitations

The EGFR test is designed to detect mutations in exon 18, 19, 20, and 21 of the EGFR gene. These mutations account for >99% of all reported EGFR mutations in NSCLC patients. Samples with results reported as "no mutation detected" may harbor EGFR mutations that are not detected by the assay.

Detection of mutation is dependent on sample integrity and the amount of amplifiable DNA present in the specimen. The methods used in this assay are highly selective and, depending on the total amount of DNA present, can detect approximately 2% to 20% of mutant in a background of wild-type genomic DNA.

This test was developed, and its performance characteristics determined, by LabCorp. It has not been cleared or approved by the US Food and Drug Administration (FDA).

Methodology

SNaPshot Multiplex PCR (primer extension-based method)

Specimen Requirements

Information on collection, storage, and volume

Specimen

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

Volume

Five unstained slides and one matching H&E-stained slide at 10 μM or formalin-fixed, paraffin-embedded tissue block

Minimum Volume

Two unstained slides and one matching H&E-stained slide at 10 μM (Note: Samples with >4 mm² and ≥50% tumor content are preferred.)

Container

Slides or blocks

Storage Instructions

Submit blocks/slides at room temperature.

Causes for Rejection

Tumor block containing insufficient tumor; tissue or tumor fixed in a heavy metal fixative; broken or stained slides