Overview: EGFR Mutation Panel
Introduction: The EGFR Mutation Panel is a diagnostic tool designed to detect EGFR mutations using tissue (FFPE) or plasma samples. In India, non-small cell lung cancer (NSCLC) accounts for ~80 percent of lung cancers (~70,000 cases/year), with EGFR mutations prevalent in 30-50 percent of adenocarcinoma cases (higher in non-smokers, females, and Asians), guiding targeted therapy with EGFR TKIs (gefitinib, osimertinib). High morbidity from under-testing in rural/low-SES patients, limited NGS labs, delayed targeted therapy leading to poor progression-free survival. Per oncology practices aligned with ICMR and Indian Society of Medical Oncology guidelines, the test employs NGS for exons 18-21 mutations over 1-2 days with high sensitivity/specificity, valuable for precision oncology in advanced NSCLC. This diagnostic falls under cancer mutation screening and targets lung cancer patients (especially adenocarcinoma), addressing accurate detection to guide first-line TKI therapy or clinical trials. With elevated morbidity due to under-testing, the test supports public health efforts by enabling precise treatment selection and improving survival. Its FFPE/plasma-based approach ensures reliable liquid biopsy capability.
Other Names: EGFR Mut Pnl.
FDA Status: FDA approved, CLIA certified for molecular pathology/oncology, compliant with 2025 standards.
Historical Milestone: EGFR testing mandatory in NSCLC; in India, expanding in oncology centers.
Purpose: The test detects 4 parameters including EGFR Exon 18 to guide mutation assessment, identify actionable variants, inform targeted therapy.
Test Parameters: 1. EGFR Exon 18, 2. Exon 19, 3. Exon 20, 4. Exon 21.
Pretest Condition: No fasting required; patients should have confirmed lung cancer diagnosis.
Specimen: FFPE tissue block (0.5-2 cm³) or 3 mL plasma in EDTA tube, transported within specified times to maintain sample viability.Sample Stability: Indefinite (FFPE) or 8 hours RT / 7 days refrigerated / 6 months frozen (plasma), though immediate processing preferred.
Medical History: Patients should provide details on cancer stage, histology, smoking history, prior therapy.
Consent: Written informed consent is required, detailing the test's purpose, potential risks of untreated actionable mutations including poor response, benefits of profiling, and minimal discomfort (tissue/plasma already collected).
Procedural Considerations: The test involves sample processing using NGS by trained personnel to ensure sterile technique, avoid contamination, and interpret results within 1-2 days using provided controls. Laboratories must maintain a controlled environment, adhere to quality assurance protocols.
Factors Affecting Result Accuracy: Poor tissue quality, low tumor content, or delays can affect results. Correlation with clinical evaluation or additional testing is recommended to confirm findings.
Clinical Significance: Actionable EGFR mutations indicate TKI eligibility, necessitating specialist input. No mutations may require follow-up.
Specialist Consultation: Medical oncologists should be consulted for management.
Additional Supporting Tests: IHC or FISH for confirmation.
Test Limitations: Covers hotspots only; comprehensive approach required.
References: Indian Journal of Medical Oncology 2024, NSCLC Studies India 2023.
