Skip to main content
TanyaKanker
BiomarkerDraft, not yet medically reviewedUpdated 2026-09-10

EGFR-Positive Lung Cancer: Test Results and Next Questions

Other names: EGFR sensitizing mutation, EGFR exon 19 deletion, EGFR L858R, EGFR exon 20 insertion

Changes in the EGFR gene can make lung cancer cells grow more aggressively; the result affects which targeted therapy categories are worth discussing.

Add my test resultClinical trials with this marker
Ilustrasi reseptor di permukaan sel dengan molekul ligan yang mendekat

What should I record from an EGFR-positive result?

EGFR is a gene that can be altered in some lung cancers. Record the exact variant written in the report; the term EGFR-positive alone does not identify the alteration.

Source: NCI: EGFR gene

Prepare these details for your consultation

  • Exact variant, such as exon 19 deletion or L858R
  • Test date, sample type and method
  • Treatment history and your main question for the doctor
Create my free preparation checklistAsk a navigator about next steps

The checklist is free, with no account or report upload. Navigator support is administrative; medical assessment and any service fees require separate confirmation.

Not a diagnosis and not final medical advice. Must be reviewed by a doctor.

Plain explanation

EGFR is a gene that regulates cell growth signals. If this gene undergoes a change (mutation), the growth signal can continue to glow. Molecular examination can find these changes in tumor tissue or, in certain cases, in blood samples.

Clinical meaning

A common EGFR mutation (exon 19 deletion, L858R) alters the way systemic therapy is selected in non-small-cell lung cancer. Other groups of mutations, including exon 20 insertions, are generally considered distinct and are often directed to other pathways, including clinical trials.

Testing methods

  • Next-generation sequencing (NGS)

    A test that reads many genes from one tumour sample to find actionable changes.

  • EGFR PCR

    A focused test that looks for specific changes in the EGFR gene.

  • Liquid biopsy (ctDNA)

    A blood test that looks for tumour genetic material to supplement or partly replace tissue testing.

  • Tumour tissue biopsy

    Collection of tumour tissue to confirm the diagnosis and provide material for further testing.

A negative result does not always mean the marker is absent

Test sensitivity differs by sample type and method. Results need to be read together with the pathology report and clinical condition.

What needs verification

  • Specific types of EGFR changes, not just positive or negative status.
  • Type of sample examined (tumor tissue or blood) and date of examination.
  • The examination method used and the laboratory that produces the results.
  • Are the results of the old examination still relevant if the tumor has developed?

Related drugs

  • Osimertinib

    Third generation EGFR tyrosine kinase inhibitor

  • Erlotinib

    First generation EGFR tyrosine kinase inhibitor

  • Gefitinib

    First generation EGFR tyrosine kinase inhibitor

  • Afatinib

    Second generation EGFR/HER2 tyrosine kinase inhibitor

  • Amivantamab

    EGFR-MET bispecific antibody

A link here means the marker is often part of considering a drug category, not a recommendation to use it.

Guides discussing this marker

Written to help prepare questions and documents, not to replace a doctor's assessment.

Discussed in cancers

Treatment categories

Sources

Clinical trials

Studies mentioning this marker

Filtered from public study descriptions. Access status and site readiness remain unverified.

Check options based on your result

Share the EGFR result you have so we can explain which categories to discuss with a doctor.

Consult via WhatsAppUpload Medical Reports

After submission, a human navigator reviews your request and contacts you through your chosen channel. The WhatsApp message already includes this page context, so you do not need to explain from the beginning.

Clinical data is not requested in the form and is not sent to analytics. Do not send medical reports through WhatsApp or email; use the secure upload page. We do not promise eligibility or any treatment outcome.

Next steps

These suggestions come from links between entries in TanyaKanker's database, not from a medical judgement. Each suggestion includes why it appears.

Next to learn

To check

What you can do

  • Upload medical reports

    Build a case summary in twelve steps

    Reason: Often the most useful next step after reading this page

  • Request a second opinion

    Review of the treatment plan

    Reason: Relevant when a treatment plan is being considered

  • Consult a navigator

    A request is recorded with this page context

    Reason: For asking the next step directly

Recently updated

Want to follow changes on this topic? Save the page or follow the topic so it is easy to find again. View saved items.

Complete pathway

EGFR after osimertinib

My treatment stopped working. What does the next step depend on?

  1. EGFR markerStarting point: what is tested and what the marker does not decide by itself.
  2. EGFR exon 19 deletionA variant that often makes EGFR inhibition relevant to discuss.
  3. OsimertinibThe drug that most often forms the context for this question.
  4. Progression after targeted therapyThe decision situation you face, not a disease name.
  5. Osimertinib resistance guideThe order of questions and steps when treatment stops working.
  6. NGS (next-generation sequencing)A test that can assess many genes from one sample, including resistance mechanisms.
  7. EGFR C797SOne resistance mechanism looked for on repeat testing.
  8. MET amplificationAnother resistance mechanism that can change the direction of discussion.
  9. EGFR T790MA mechanism where treatment sequence matters.
Upload medical reportsSearch EGFR clinical trialsOpen marker result explainer

A structured summary so repeat testing and treatment history are readable.

Prepare for your next consultation

Use the free six-question tool to prepare questions for your doctor.

Start free · 6 questionsContact a navigatorSaved pages