EGFR Gene Mutation Analysis

Function

The Epidermal Growth Factor Receptor (EGFR) is a protein on the surface of cells that helps them grow and divide. Mutations in the EGFR gene can cause the receptor to be constantly 'turned on,' leading to the uncontrolled cell growth characteristic of cancer. This test uses molecular techniques (like PCR or Next-Generation Sequencing) to identify specific mutations in exons 18, 19, 20, and 21 of the EGFR gene.

Why it is Ordered

This test is a critical component of 'Personalized Medicine' for patients diagnosed with Non-Small Cell Lung Cancer (NSCLC), particularly adenocarcinoma. Knowing the mutation status allows oncologists to determine if the patient will respond to targeted therapies known as Tyrosine Kinase Inhibitors (TKIs), such as erlotinib, gefitinib, or osimertinib. Patients with specific mutations often respond significantly better to these drugs than to traditional chemotherapy.

Associated Conditions

• Non-Small Cell Lung Cancer (NSCLC): The primary condition where this test is utilized.
• Acquired Resistance: Tests are often repeated (e.g., looking for the T790M mutation) if a patient stops responding to their initial targeted therapy.