Skip to content

EGFR Gene Mutation Test, Blood

Published: August 9, 2026Updated: August 17, 2026

A blood-based genetic test that checks for selected changes, called mutations, in the EGFR gene.

Quick summary

["The test can help identify EGFR mutations that may affect cancer treatment or inherited genetic risk."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 17, 2026Editorial policy

Key facts at a glance

LOINC
21666-3
Short code
EGFR gene Mut Tested Bld/T
Synonyms
EGFR gene Mut Tested Bld/T
Category
kidney
Sample
whole-blood
Container
Lavender-top (EDTA)
Units
N/A
Ref low
90
Ref high
120
Critical range
15 N/A – —
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
molgen
CPT
82565
SNOMED
247997009
Specimen volume
3 mL
Stability
Room temperature: 4h, Refrigerated: 24h
Hemolysis max
0
Lipemia max
0
Icterus max
0
TAT
4–24 hours
Order
routine

What is this test?

This test examines a blood sample for mutations in the EGFR gene. Depending on the laboratory method, it may analyze DNA from white blood cells or circulating tumor DNA.

Why might I need this test?

EGFR testing may be used to help select targeted cancer treatment, monitor treatment response, or evaluate a possible inherited genetic condition. The reason for testing and the type of blood analysis vary by the ordered panel.

How is the test performed?

A blood sample is collected and tested in a laboratory using specialized genetic analysis. The laboratory reports whether relevant EGFR mutations were detected and may identify the specific variant.

How do I prepare for the test?

No special preparation is usually required. Follow any instructions from your healthcare professional, and tell the laboratory if you recently received a blood transfusion or are taking blood-thinning medicines.

Reference range

Normal: >90 mL/min/1.73m²N/A

Specimen: whole-blood

No special preparation required. Stay well hydrated.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

EGFR Mutation Test

Frequently asked questions

Does a positive EGFR mutation result mean I have cancer?
No. A positive result only means that a tested EGFR variant was detected. Other clinical information is needed to determine whether it is inherited, associated with an existing cancer, or clinically significant.
Can this test replace testing of a tumor sample?
It depends on the test and clinical situation. Blood-based testing may be less sensitive than direct testing of a tumor sample, so your healthcare professional may recommend additional testing.
Will the test identify every possible EGFR mutation?
No. Most tests examine selected mutations or common variant regions. The laboratory can explain which alterations the ordered test is designed to detect.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy