EGFR (epidermal growth factor receptor) (eg, non-small cell lung cancer) gene analysis, common variants (eg, exon 19 LREA deletion, L858R, T790M, G719A, G719S, L861Q)

CPT4 code

Name of the Procedure:

EGFR (Epidermal Growth Factor Receptor) Gene Analysis (Common Variants: Exon 19 LREA Deletion, L858R, T790M, G719A, G719S, L861Q)

Summary

The EGFR Gene Analysis is a laboratory test that examines specific mutations in the epidermal growth factor receptor (EGFR) gene. It is particularly important for patients with non-small cell lung cancer. By identifying these mutations, doctors can tailor treatments to the genetic profile of the tumor.

Purpose

The primary purpose of EGFR gene analysis is:

To identify mutations in the EGFR gene that are commonly associated with non-small cell lung cancer (NSCLC).
To help guide the selection of personalized cancer treatments, such as tyrosine kinase inhibitors (TKIs), which target specific EGFR mutations.

Indications

This test is indicated for patients who:

Have been diagnosed with non-small cell lung cancer.
Demonstrate symptoms or have clinical features suggesting the presence of EGFR mutations.
Have progressed after initial lung cancer treatments and require additional therapeutic guidance.

Preparation

Before the procedure, the patient should:

Provide a tissue or blood sample, which the healthcare provider will collect.
No specific fasting or medication adjustments are generally required unless specified by the healthcare team.
Complete any diagnostic imaging or biopsies as recommended by the oncologist to locate the tumor and plan the biopsy if necessary.

Procedure Description

The procedure involves:

Sample Collection: A tissue biopsy or blood sample is obtained from the patient.
DNA Extraction: DNA is extracted from the collected sample.
PCR Amplification and Sequencing: Polymerase Chain Reaction (PCR) is used to amplify the EGFR gene, followed by DNA sequencing to identify specific mutations.
Data Analysis: The generated data is analyzed to detect the presence of mutations such as exon 19 LREA deletion, L858R, T790M, G719A, G719S, and L861Q.
Tools and Equipment:
- Biopsy needles, syringes for sample collection.
- PCR machines, sequencers, and specialized reagents for DNA analysis.

Anesthesia:

Local anesthesia may be used during tissue biopsy procedures.

Duration

The entire testing process, from sample collection to result analysis, typically takes a few days to a couple of weeks.

Setting

The sample collection occurs at a hospital, outpatient clinic, or specialized surgical center. The DNA analysis is conducted in a specialized laboratory.

Personnel

Oncologists and pulmonologists may order the test.
Pathologists and laboratory technicians perform the DNA extraction and analysis.
Nurses and radiologists are involved in the sample collection process.

Risks and Complications

Sample Collection Risks: Bleeding, infection, and pain at the biopsy site.
Procedural Risks: There are minimal risks directly from the genetic test itself, but incorrect sampling or handling can lead to inconclusive or false results.

Benefits

Personalized treatment plans can significantly improve patient outcomes.
Better response rates to targeted therapies based on the specific EGFR mutation.
Reduced exposure to ineffective treatments.

Recovery

Post-procedure care mainly applies to biopsy recovery, which may include managing soreness and monitoring for infection.
No recovery time is required for the genetic test itself, and patients can resume normal activities immediately.
Follow-up appointments with an oncologist are necessary to discuss the results and subsequent treatment plans.

Alternatives

Liquid Biopsy: A non-invasive alternative using blood samples to detect EGFR mutations.
Broad Genetic Testing Panels: These may assess multiple genes involved in cancer, not just EGFR.
Pros and Cons:
Liquid Biopsy: Less invasive but might not be as comprehensive.
Broad Genetic Testing Panels: Provide extensive information, which can be beneficial but more costly and time-consuming.

Patient Experience

During the Procedure: Patients may feel discomfort or pain during a biopsy; however, local anesthesia helps manage these sensations.
After the Procedure: Mild soreness at the biopsy site; genetic testing itself involves no discomfort.
Pain Management: Pain relief may include over-the-counter pain medications and ice packs at the biopsy site. Comfort measures during the biopsy include numbness, local anesthesia, and supportive care by medical staff.