EGFR stands for epidermal growth factor receptor. It’s a protein found on healthy cells.
When cancer cells test positive for EGFR, it means the gene contains a mutation and is sending faulty instructions to the cells, allowing cancer to grow and spread.
Read on as we explore the specifics of EGFR lung cancer and how this mutation affects treatment.
A mutation is an error in a specific part of DNA. These errors, also known as biomarkers, make cells behave abnormally.
EGFR is a protein that helps cells grow and divide. Certain errors cause cells to grow and divide at an unusually high rate, leading to cancer.
In lung cancer, the most common EGFR errors are EGFR 19 deletion and EGFR L858R point mutations. These mutations respond to targeted therapies called tyrosine kinase inhibitors (TKIs).
Less common EGFR mutations, like EGFR exon 20 insertions, don’t usually respond to TKIs.
There are three main types of NSCLC:
- Adenocarcinomas. Adenocarcinomas form in the outer area of the lung and make up 60 percent of all NSCLC cases.
- Squamous cell carcinoma. Squamous cell carcinoma is another type of NSCLC that usually forms near bronchial tubes and makes up 30 to 35 percent of NSCLC cases.
- Large cell carcinoma. This type of cancer can start anywhere in the lungs and is rarer than the previous two types.
In general, large cell carcinoma tends to spread faster than adenocarcinoma or squamous cell carcinoma.
Worldwide, about 32.4 percent of NSCLCs involve EGFR mutations.
EGFR mutations are more common among:
- people with lung adenocarcinoma compared with other subtypes of NSCLC
- never smokers or light smokers
- young adults
- people of Asian descent
Risk factors for lung cancer in general include:
- genetic risk factors
- air pollution exposure
- occupational exposures such as asbestos, metals, and diesel fumes
It’s important to note that about 10 to 15 percent of people with lung cancer have never smoked.
Symptoms of EGFR lung cancer are the same as other types of lung cancer. You might not have any symptoms in the early stages, but these early symptoms may include:
- chest pain
- shortness of breath, wheezing
- frequent bronchitis, pneumonia, or other lung infections
- coughing up blood
These symptoms should not be ignored. Only about 17 percent of lung cancers are diagnosed at a localized stage when it’s easier to treat.
As the disease spreads, symptoms can include:
When to schedule a medical appointment
It’s easier to treat cancer before it spreads. Schedule an appointment with a healthcare professional as soon as possible if you have:
- persistent cough or raspy voice
- wheezing and shortness of breath
- chest pain
If you smoke, ask a doctor if you should have regular lung cancer screenings.
When being evaluated for lung cancer, your appointment will likely start with a physical exam and collecting your medical history. Imaging tests may include:
A lung cancer diagnosis can be confirmed with a biopsy. That’s also how the cancer is tested for specific gene mutations, now a routine part of diagnosing and staging lung cancer.
There are several ways to get a tissue sample, including:
In 2016, the
Treatment for lung cancer depends on stage and type. Treatment may include:
In most cases, chemotherapy is not a first-line treatment for lung cancer with EGFR mutations.
The main treatment is likely to be targeted therapy. Medications approved for EGFR-positive lung adenocarcinoma include:
- afatinib (Gilotrif)
- dacomitinib (Vizimpro)
- erlotinib (Tarceva)
- gefitinib (Iressa)
The most recent addition is osimertinib (Tagrisso). In 2020, the
These are all oral medications called tyrosine kinase inhibitors. They work by blocking the activity of the EGFR protein.
Therapy for advanced EGFR lung cancer
EGFR lung cancer eventually becomes resistant to a drug that has been working. When that happens, your doctor may switch to another approved treatment. Additional testing for biomarkers may open the door to more options.
In advanced NSCLC, erlotinib can be combined with an angiogenesis inhibitor. These drugs block the growth of new blood vessels that help fuel cancer. They are:
- bevacizumab (Avastin)
- ramucirumab (Cyramza)
These monoclonal antibodies can also be combined with chemotherapy.
An EGFR inhibitor called necitumumab (Portrazza) is used to treat squamous cell NSCLC. This is also a monoclonal antibody, but it’s given by IV infusion. It can be used alongside chemotherapy in advanced squamous cell NSCLC.
Some of the common side effects of EGFR inhibitors are:
- loss of appetite
- mouth sores
- rash on the face and chest
- skin infections
When diagnosed in later stages, the goal of treatment is to slow disease progression and improve quality of life.
Lung cancer is treatable. The outlook for people with EGFR lung cancer is improving with the use of targeted therapies. However, while EGFR inhibitors can control cancer progression for months or years, it’s not a cure.
According to the American Cancer Society, the 2-year relative survival rate for NSCLC was 34 percent for diagnoses in 2009 through 2010. It increased to 42 percent in 2015 through 2016.
The 5-year relative survival rate for NSCLC is 25 percent.
When looking at lung cancer statistics, it’s important to remember that they’re a glance into the past. These statistics reflect diagnoses and treatments from at least 5 years ago, if not more. That’s before some TKIs were approved.
Your prognosis depends on a variety of factors, such as your:
- stage at diagnosis
- age and overall health
- response to treatment
Your doctor will review all of your medical information and give you a clearer picture of what to expect.