The epidermal growth factor receptor (EGFR) is a protein that sometimes appears in high amounts on the surface of cancer cells and helps them grow.12
Some lung cancer cells have a DNA mutation that affects the EGFR. This is known as having a tumour that is EGFR mutation-positive.23
Mutated EGFRs show an increased rate of uncontrolled tumour growth, which can speed up the cancer’s progression.23
Importance of knowing mutation status
It is important to know the EGFR mutation status because it can help doctors select the most appropriate treatment for a patient.
Cancer cells with mutated EGFRs (mutation-positive) are constantly signalling the tumour to grow and are therefore, very sensitive to cancer treatments known as targeted therapies such as the Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor (EGFR-TKI) therapy.23
In advanced NSCLC, there are two main treatment options: chemotherapy and targeted therapy. Medical studies have shown that patients with EGFR mutation-positive tumours gain more benefit from targeted therapies than with standard chemotherapy,23 while patients with EGFR mutation-negative tumours gain more benefit from chemotherapy than with targeted therapies.23
Factors that may be predictors of EGFR Mutations
There are some factors that may predict how likely an individual is to have an EGFR mutation. For example, EGFR mutations are more likely to be observed in:23
- Patients with adenocarcinomas (the most common subtype of non-small cell lung cancer – about 40% of NSCLC)
- Nonsmokers (or ex-light smokers)
- Those of Asian descent
People diagnosed with advanced NSCLC should talk to their doctor about EGFR mutation testing. The only way to find out if a tumour is EGFR mutation-positive and select the most appropriate treatment for a patient is to have an EGFR mutation test. See EGFR Mutation Testing section for more information.
12. ACS. Tests for Non-Small Cell Lung Cancer. Available at: https://www.cancer.org/cancer/non-small-cell-lung-cancer/detection-diagnosis-staging/how-diagnosed.html. Accessed 2: May 2019.
23. QLA. Important Information for People with Advanced Non-Small Cell Lung Cancer. Available at: http://www.lungcancercanada.ca/LungCancerCanada/media/Documents/IRE-09007E-PatientSite.pdf. Accessed: 3 May 2019.