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Test ID: EGFRX    
Lung Cancer, EGFR with ALK Reflex, Tumor

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

All specimens will undergo EGFR testing. The EGFR test is an FDA-approved PCR-based kit employing Scorpions real-time PCR and allele-specific PCR technologies that is used to test for common mutations within exons 18 through 21 of the EGFR gene, the following mutations will be detected:

 

Mutation

Exon

Base Change

G719A*

18

c. 2156G>C

Deletions

19

c.2238_2255del18

c.2235_2249del15

c.2235_2250del15

c.2239_2253del15

c.2239_2256del18

c.2240_2254del15

c.2240_2257del18

c. 2239_2248TTAAGAGAAG>C

c.2239_2251>C

c.2237_2255>T

c.2239_2258>CA

c.2238_2252>GCA

c. 2238_2248>GC

c. 2235_2252>AAT

S768I

20

c. 2303G>T

Insertions

20

c. 2319_2320insCAC

c. 2310_2311insGGT

T790M

20

c. 2369C>T

L858R

21

c. 2573T>G

L861Q

21

c. 2582T>A

*While this test was designed to evaluate for the G719A alteration, cross-reactivity with other alterations at the G719 codon have been described.

 

A pathology review and macro dissection to enrich for tumor cells are performed prior to DNA extraction.(Package insert: THERASCREEN EGFR RGQ PCR Kit Instructions for Use (Handbook). Version 1. July 2013).

In patients with no detectable EGFR mutations, ALK FISH testing will be performed. The ALK FISH test uses an FDA-approved ALK dual-color, break-apart rearrangement probe kitset. The ALK probe consists of 2 probes that flank the ALK gene region at 2p23 (Abbott Molecular). Five micron sections of formalin-fixed, paraffin-embedded tissue specimens are cut and mounted on positively charged glass slides. The selection of tissue and the identification of target areas on the hematoxylin and eosin-stained slide are performed by a pathologist. The probe set is hybridized to the appropriate target areas and 2 technologists analyze 25 interphase nuclei each (50 total). Results are reported based on the guidelines include with the probe kit and package insert with the results expressed as the percent abnormal nuclei.(Unpublished Mayo method)

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

No

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

Monday through Friday; 10 a.m.

Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.

5 days (EGFR only) 10 days (if ALK is added on)

Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result

7 days (EGFR only) 14 days (if ALK is added on)

Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

Unused portions of blocks will be returned. Slides are stored indefinitely.

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

Rochester