EGFR is shorthand for epidermal growth factor receptor. It’s a protein that tells cells when to grow and divide. When there’s a mutation, or change, in its DNA, the messages it sends your cells change. This can lead to the growth of cells that cause cancer. In the U.S., about 85% of all lung cancers are non-small-cell lung cancers (NSCLCs), and roughly 15% of all lung cancers have an EGFR-positive mutation. 

 

There are more than 70 EGFR mutations. Many are either additions (“insertions”) to or subtractions (“deletions”) from the EGFR DNA genetic code. It’s critical for your treatment that your medical team first pinpoints your specific mutation. Certain rare mutations don’t respond to the drugs given for the more common ones.

Biomarker tests show what kind of EGFR mutation you have. You might have already had a biomarker test on a tissue sample, or biopsy, from your lung. This is the main way to find out the genetic makeup of your tumor. Your doctor may also do a test called a blood or liquid biopsy on a blood sample. A liquid biopsy technique called NGS, or next-generation sequencing, can test for several biomarkers at once with a small sample.
 

The stage of your EGFR-positive NSCLC is another important clue to help guide your treatment. Stages range from occult (or hidden) to 0 to IV, with many sub-stages. Treatments vary by stage and even by sub-stage.

The stage of your cancer will guide your treatment. If possible, treatment starts with surgery to remove the tumor. You may take targeted medications called EGFR inhibitors that block the faulty signals that tell cancer cells to grow. These may be tyrosine kinase inhibitors (TKIs) that you take by mouth or monoclonal antibodies that you get as an IV. Chemotherapy, radiation, and immunotherapy are also options. 
 

In early stages, surgery may be able to cure the cancer. In late stages, the goal is to slow its growth to extend survival time from months to years. The time frame is longer for the most common mutations but shorter for rarer ones. In the latest stages, your treatment will focus on keeping you comfortable and giving you the best possible quality of life. 
 

Researchers are constantly looking for treatments that work better for all mutations, including better versions of EGFR inhibitors like TKIs. One possibility is a combination therapy that pairs immunotherapy with chemotherapy. 
 

Ask about the common side effects of EGFR inhibitors so you can be better prepared. They include skin reactions like a pimply rash, dry skin, itchiness, or changes to hair and nails. This is because these drugs also change the way skin cells function. Many people get diarrhea, which can lead to dehydration and weakness if severe. Mouth sores and loss of appetite are also possible.

It’s very common for EGFR lung cancer to spread, or metastasize, to the brain. Ask about symptoms you might have and tests to look for signs of these brain metastases. Because some of the drugs that target EGFR can cross the blood-brain barrier, they can treat lung cancer that has spread to the brain. Some brain metastases are treated directly with radiation.
 

Depending on your specific type of EGFR-positive NSCLC, you might be a candidate for one of the many clinical trials for new lung cancer treatments. People in a clinical trial usually get either the standard treatment or the new treatment under investigation. Ask your doctor about trials that you may qualify for.
 

EGFR inhibitors can often control lung cancer for several months or even years. But cancer cells are always changing. They often become resistant to cancer drugs. This is called acquired resistance. If this happens, ask if your doctor could repeat a biomarker test to look for a new mutation that might respond to another drug. Some people with lung cancer that progresses benefit from platinum-based chemotherapy.