Thanks to advances in modern medicine, doctors are learning more about lung cancer every day. They can now run tests to look for biomarkers — genetic signs that can give more information about a person’s cancer. One of these biomarkers is epidermal growth factor receptor (EGFR), a gene that may be mutated (changed) in some people with lung cancer. If your test comes back positive for a mutation in EGFR, your doctor will tell you that you have EGFR-positive lung cancer.

Although being diagnosed with EGFR-positive lung cancer may leave you feeling confused, you can start here to learn more. This article will cover key things to know about EGFR-positive lung cancer and how it can differ from other types of lung cancer. By understanding more about this diagnosis, you can learn what questions to ask your doctor about what you might expect on your cancer journey.

1. EGFR Mutations Are Common in Lung Cancer

EGFR is a protein that can be found in many cells, and it can interact with other proteins to help different cells “talk” to each other using specific signals. The signals sent between cells are important for many processes in the body. When EGFR is working properly, it helps tell cells to grow at the right time and place. However, if there’s a mutation in EGFR, the cells are signaled to grow abnormally, resulting in lung cancer.

To make the EGFR protein, your body uses instructions from the EGFR gene in your DNA. The gene is made up of several smaller parts called exons. If a mutation happens in an exon, this can mess up the instructions in the EGFR gene and cause problems with the EGFR protein. In lung cancer, the EGFR gene is usually mutated in a few specific exons, namely exons 19, 20, and 21.

Although lung cancer is associated with mutations in many different genes, EGFR mutations are among the most common.

2. People Who Don’t Smoke Can Develop EGFR-Positive Lung Cancer

Generally, EGFR-positive lung cancer is non-small cell lung cancer (NSCLC), which is the most common type of lung cancer. NSCLC can be further broken down into subtypes, the most common of which is lung adenocarcinoma. About 15 percent to 20 percent of lung adenocarcinoma cases are EGFR-positive.

It’s possible for EGFR-positive lung cancer to run in families because EGFR mutations are sometimes passed down from parents to their children. Although lung cancer, in general, is more often diagnosed in older adults, people who inherit an EGFR mutation may get lung cancer earlier in life.

Smoking is the main risk factor for lung cancer, but many people who have never smoked have EGFR mutations. EGFR-positive lung cancer is also more likely to affect females and people of East Asian descent, although other ethnic groups can be affected as well.

3. Different Types of Biopsies and Testing Are Available

To test your cancer for certain biomarkers, your doctor will need to collect a sample — or biopsy — of lung cancer cells. In some cases, they may perform a tissue biopsy, which involves performing surgery to remove a piece of the tumor for testing. If you’re unable to undergo that procedure, they may take a blood sample and collect the tumor cells in the blood. This liquid biopsy is faster and less invasive than a tissue biopsy.

Following a biopsy, different techniques may be used for biomarker testing. For example, next-generation sequencing (NGS) can look at all your DNA and find mutations in specific genes. NGS can be done only with a tissue biopsy that has enough tumor cells to get a good result. If there aren’t enough cells, a technique like polymerase chain reaction (PCR) can be used instead. PCR tests a specific gene and can be used to find common EGFR mutations in lung cancer.

4. Targeted Therapies Exist for EGFR-Positive Lung Cancer

If EGFR-positive lung cancer is diagnosed in the earlier stages of disease, surgery may be the initial treatment. However, EGFR-positive lung cancer is more commonly diagnosed during a more advanced stage. In most cases, the first treatment will be targeted therapy, which uses drugs that recognize a specific protein or group of proteins. The targeted therapy drugs that are used to treat EGFR-positive lung cancer are called tyrosine kinase inhibitors (TKIs). Your doctor may prescribe different TKIs depending, in part, on what type of EGFR mutation you have.

Some targeted therapies have been used to treat EGFR-positive lung cancer for many years. These are known as first-generation TKIs and include the drugs erlotinib (Tarceva) and gefitinib (Iressa). First-generation TKIs are used to treat people with EGFR mutations in exon 19 or 21. If you’re positive for either of these mutations, your doctor may prescribe one of these drugs first.

Newer targeted therapy drugs, such as second-generation TKIs, have been developed more recently to treat EGFR-positive lung cancer. Second-generation TKIs include dacomitinib (Vizimpro) and afatinib (Gilotrif), which may be more effective than first-generation TKIs.

Additionally, the third-generation TKI osimertinib (Tagrisso) may be suggested for people whose cancer didn’t respond after treatment with first-generation TKIs. Osimertinib also may be given as the first line of treatment in EGFR-positive lung cancer, and it has fewer side effects than other TKIs.

Although not typically used for EGFR-positive lung cancer, chemotherapy may be used in cases where the cancer doesn’t respond well to TKIs.

Other types of targeted therapies might also be used to treat EGFR-positive lung cancer. Drugs called vascular endothelial growth factor (VEGF) inhibitors may be combined with TKIs to treat some cancers. Immunotherapy, which includes drugs that interact with the immune system, isn’t used to treat most cases of EGFR-positive lung cancer. However, it may be explored as an option for people whose tumors have less-common EGFR mutations.

5. Treatment May Give You a Better Quality of Life

TKIs are effective for many people with EGFR-positive lung cancer and can improve their prognosis (outlook) compared to that of people without EGFR mutations. Several studies have shown that, following treatment, people with EGFR-positive lung cancer can go longer periods without their cancer getting worse. Although overall survival isn’t necessarily longer, a better treatment response can mean fewer symptoms and a better quality of life.

TKIs may work at first, but most people eventually stop responding to therapy, and the cancer continues to grow. Because of this, the overall survival for EGFR-positive lung cancer is about one to two years after diagnosis. More research is needed to find better treatments and lead to longer lives for people with EGFR-positive lung cancer.

Depending on how you respond to treatment, your doctor may give you the option to participate in a clinical trial to explore how well new targeted therapies work against EGFR-positive lung cancer. This may give you an opportunity to benefit from new therapies and have more time with your loved ones.

Talk With Others Who Understand

MyLungCancerTeam is the social support network for people with lung cancer and their loved ones. On MyLungCancerTeam, more than 12,000 members come together to ask questions, give advice, and share their stories with others who understand.

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