Test Catalog

Test Id : T790M

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Cell-Free DNA EGFR T790M Mutation Analysis, Blood

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Overview

Test Catalog

Useful For
Suggests clinical disorders or settings where the test may be helpful

Determination of EGFR T790M mutation status in blood specimens as an alternative to invasive tissue biopsies

 

Identification of patients with non-small cell lung cancer who harbor a T790M mutation and may benefit from specific epidermal growth factor receptor (EGFR)-targeted therapies

Genetics Test Information
Provides information that may help with selection of the correct genetic test or proper submission of the test request

This test evaluates cell-free DNA (cfDNA) in whole blood for the presence of the EGFR T790M mutation in patients with non-small cell lung cancer (NSCLC) and can be used to assess eligibility for targeted therapies. Current data suggests that patients with metastatic NSCLC and the T790M mutation may benefit from T790M-targeted therapy (eg, osimertinib).

 

This test is not validated for serial monitoring of patients with cancer. This test is also not intended as a screening test to identify cancer.

Highlights

This test evaluates whole blood for the presence of the T790M mutation in the EGFR gene in cell-free DNA

 

This test provides rapid detection of the EGFR T790M mutation in non-small cell lung cancer patients as an alternative for EGFR analysis of tissue.

Method Name
A short description of the method used to perform the test

Droplet Digital Polymerase Chain Reaction (PCR)

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.

Yes

Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

cfDNA EGFR T790M Test, Blood

Aliases
Lists additional common names for a test, as an aid in searching

NSCLC

Non-small cell lung cancer

Lung cancer

EGFR

Epidermal growth factor receptor

Cell free DNA

cfDNA

Circulating tumor DNA

Liquid biopsy

Circulating tumor cells

T790M

Cell-free DNA

Specimen Type
Describes the specimen type validated for testing

Whole blood

Ordering Guidance

This test is not a prenatal screening test.

 

This test detects only the T790M mutation in the EGFR gene. It does not detect other EGFR gene mutations in exons 18 through 21.

 

This test provides rapid detection of the EGFR T790M mutation in whole blood specimens from non-small cell lung cancer patients as an alternative for EGFR analysis of tissue. For tissue testing, order EGFRS / EGFR Gene, Targeted Mutation Analysis, 51 Mutation Panel, Tumor.

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Supplies: Streck Black/Tan Top Tube Kit (T715)

Container/Tube: 10-mL Streck cell-free DNA (cfDNA) tubes

Specimen Volume: Two 10-mL Streck cfDNA tubes

Additional Information: Only blood collected in Streck Cell-Free DNA BCT will be accepted for analysis. Whole blood will be processed to produce platelet poor plasma before cfDNA isolation.

Forms

If not ordering electronically, complete, print, and send an Oncology Test Request (T729) with the specimen.

Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the Testing Laboratory

One 10 mL Streck tube

Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected

All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.

Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen Type Temperature Time Special Container
Whole blood Ambient (preferred) 7 days Streck Black/Tan top
Refrigerated 7 days Streck Black/Tan top

Useful For
Suggests clinical disorders or settings where the test may be helpful

Determination of EGFR T790M mutation status in blood specimens as an alternative to invasive tissue biopsies

 

Identification of patients with non-small cell lung cancer who harbor a T790M mutation and may benefit from specific epidermal growth factor receptor (EGFR)-targeted therapies

Genetics Test Information
Provides information that may help with selection of the correct genetic test or proper submission of the test request

This test evaluates cell-free DNA (cfDNA) in whole blood for the presence of the EGFR T790M mutation in patients with non-small cell lung cancer (NSCLC) and can be used to assess eligibility for targeted therapies. Current data suggests that patients with metastatic NSCLC and the T790M mutation may benefit from T790M-targeted therapy (eg, osimertinib).

 

This test is not validated for serial monitoring of patients with cancer. This test is also not intended as a screening test to identify cancer.

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Epidermal growth factor receptor (EGFR)-targeted tyrosine kinase inhibitors (eg, gefitinib and erlotinib) have been approved by the US Food and Drug Administration (FDA) for use in treating patients with non-small cell lung cancer (NSCLC) who previously failed to respond to traditional chemotherapy. However, the EGFR T790M mutation is associated with acquired resistance to tyrosine kinase inhibitor (TKI) therapy in about 60% of patients with disease progression after initial response to erlotinib, gefitinib, or afatinib. Recent data suggest that patients with metastatic NSCLC and the T790M mutation may benefit from osimertinib, an FDA-approved oral TKI that inhibits both EGFR-activating mutations and the T790M mutation.

Interpretation
Provides information to assist in interpretation of the test results

An interpretive report will be provided.

Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

Patients with a negative test result may still harbor the EGFR T790M mutation. Mutation testing of a tissue specimen for EGFR mutations should be considered for patients with a negative result with this test.

 

The limit of detection of this assay for the detection of EGFR mutations is influenced by the amount of cell-free DNA in the blood. This is a biological variable that cannot be controlled.

 

This assay was designed to detect the following T790M mutation in the EGFR gene.

 

This test has not been clinically validated for use as a tool to monitor response to therapy or for early detection of tumors.

 

This test cannot differentiate between somatic and germline alterations.

Supportive Data

This test has been evaluated by our laboratory as an alternative to assessing paraffin-embedded tumor specimens for the EGFR T790M mutation in patients with non-small cell lung cancer.

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Schwarzenbach H, Hoon DS, Pantel K: Cell-free nucleic acids as biomarkers in cancer patients. Nat Rev Cancer 2011;11(6):426-437

2. Ettinger DS, Wood DE, Aisner DL, et al: Non-Small Cell Lung Cancer, Version 5.2017, NCCN Clinical Practice Guidelines in Oncology. J Natl Compr Canc Netw. 2017;15(4):504-535

3. Janne PA, Yang JC, Kim DW, et al: AZD9291 in EGFR inhibitor-resistant non-small-cell lung cancer. N Engl J Med. 2015;372(18):1689-1699

Method Description
Describes how the test is performed and provides a method-specific reference

Blood samples are collected in Streck Cell-Free DNA BC Tubes. Cell-free DNA is isolated from double spun plasma and assessed for the presence of the EGFR T790M mutation using digital droplet polymerase chain reaction.(Unpublished Mayo method)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information

No

Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

Monday through Friday

Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

5 to 10 days

Performing Laboratory Location
Indicates the location of the laboratory that performs the test

Rochester

Fees
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

  • Authorized users can sign in to Test Prices for detailed fee information.
  • Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
  • Prospective clients should contact their Regional Manager. For assistance, contact Customer Service.

Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.

81235

LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.

Test Id Test Order Name Order LOINC Value
T790M cfDNA EGFR T790M Test, Blood 55769-4
Result Id Test Result Name Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
113411 Result Summary 50397-9
113412 Result 55769-4
113413 Interpretation 69047-9
113414 Additional Information 48767-8
113415 Specimen 31208-2
113416 Source 31208-2
113417 Released By 18771-6

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports