By identifying specific genetic mutations and molecular markers in cancer cells, doctors can tailor treatment plans for each patient — an approach known as precision or personalized medicine.
This blog explores how genetic testing works, who needs it, and how it influences treatment decisions in lung cancer care.
What is Genetic Testing in Lung Cancer?
Genetic testing in lung cancer involves analyzing cancer cells to detect mutations or alterations in specific genes. These mutations drive cancer growth and help doctors understand which therapies might be most effective.
Genetic tests may examine:
1. DNA mutations
2. Gene rearrangements or fusions
3. Amplifications (extra copies of a gene)
4. Protein expression levels
This differs from hereditary genetic testing (used to assess inherited risk), as it focuses on somatic mutations — those acquired in the tumor, not passed from parent to child.
Why is Genetic Testing Important?
Lung cancer, especially non-small cell lung cancer (NSCLC), is not a one-size-fits-all disease. Tumors can vary significantly based on their genetic makeup. Identifying the genetic mutation behind a tumor can help doctors:
1. Choose targeted therapy
2. Avoid ineffective treatments
3. Predict response to immunotherapy
4. Plan next steps if resistance develops
Patients with mutations benefit from targeted treatments that often cause fewer side effects than traditional chemotherapy.
Common Gene Mutations Tested in Lung Cancer
Several key mutations have been identified in lung cancer. Testing for these helps personalize treatment:
Note: Not all patients will have these mutations, and some may have more than one.
How is Genetic Testing Performed?
Genetic testing is done on tissue or blood samples:
1. Biopsy Sample
1. A tumor tissue sample is collected via needle biopsy or surgery.
2. Sent to the lab for next-generation sequencing (NGS) or PCR-based testing.
2. Liquid Biopsy
1. A less invasive method using a blood sample.
2. Detects circulating tumor DNA (ctDNA) in the bloodstream.
3. Useful when a tumor biopsy isn’t possible.
4. Results usually take 1–2 weeks, and the findings guide therapy selection.
Benefits of Genetic Testing
1. Improved treatment accuracy
2. Longer progression-free survival
3. Fewer side effects
4. Better quality of life
5. Reduced trial-and-error in therapy selection
Patients who receive therapies matched to their genetic profile often experience better outcomes than those on standard treatment.
Final Thoughts
Genetic testing in lung cancer is revolutionizing treatment by replacing a “one-size-fits-all” approach with personalized precision care. It provides valuable insight into how the cancer behaves and what treatments are most likely to work.
If you or a loved one is diagnosed with lung cancer, ask your oncologist about genetic testing. It could open the door to therapies that are more effective and less toxic — offering hope in an otherwise challenging diagnosis.
