Tertiary lymphoid structures in diseases: immune mechanisms and therapeutic advances
What You Need To Know About Genetic Testing For Lung Cancer
Genetic testing helps determine whether any specific gene mutations are driving your lung cancer. Once a mutation is identified, a doctor may modify your cancer treatment to target it.
A genetic mutation in the lungs can cause non-small cell lung cancer (NSCLC). Different mutations can affect your treatment decisions and outcomes.
Genetic testing after a diagnosis of NSCLC is important because it helps your doctor personalize your treatment. Genetic testing isn't currently useful in small cell lung cancer.
Other names for genetic testing include:
Many mutations involved in NSCLC have already been identified. This has helped researchers develop drugs that target some of those specific mutations.
Knowing which mutations are driving your cancer can also give your doctor an idea of how the cancer will behave. This can help determine which drugs are most likely to be effective and which are unlikely to help.
Continue reading to learn more about the different types of genetic tests available for NSCLC, how doctors conduct them, and the kind of information they provide.
In your initial cancer biopsy, a pathologist takes a sample of your lung tissue and checks it for the presence of cancer. Often, some of the tissue samples from this biopsy can be used for genetic testing.
If there's not enough of the tissue sample left over from your initial biopsy, the pathologist may take a blood sample and test it for gene mutations. This is known as a liquid biopsy.
Other genetic tests are described below.
Fluorescence in situ hybridization (FISH)
In the fluorescence in situ hybridization (FISH) technique, a pathologist takes human-made pieces of DNA and adds them to a tissue or cell sample.
These DNA pieces contain fluorescent molecules. They only bind to certain parts of the chromosomes in the tissue or cell sample.
When the pathologist views the sample under a special fluorescent microscope, the areas where the DNA pieces have attached to the chromosomes will light up or glow. This can reveal where certain genes, such as those that have mutated, are located.
In addition, the FISH technique can reveal if:
The FISH technique can also help diagnose noncancerous conditions, such as infections.
Immunohistochemistry
Immunohistochemistry is a versatile staining technique. It uses human-made antibodies to reveal whether gene mutations or other biomarkers are present on the surface of your cells.
An antibody is a type of protective immune protein. An antigen is a foreign substance, such as a protein or bacteria, that triggers an immune response in the body.
Every antibody naturally recognizes and binds to particular antigens. The antibodies used in some forms of immunohistochemistry are engineered to bind to antigens involved in cancer.
The human-made antibodies are added to a sample of your cells. Cancer cells turn a particular color when the antibodies attach to antigens involved in cancer. This makes it easier for the pathologist to see which antigens are present.
This technique is more widely available than FISH, but FISH produces more accurate test results.
Next-generation sequencing (NGS)
DNA sequencing is a method of examining a DNA sample and verifying the proper order of each DNA building block.
If any of these building blocks appear out of sequence, it could be evidence of a gene change, such as a mutation.
In next-generation sequencing (NGS), the sample is run through a machine that can process multiple DNA sequences at once. It's much faster than traditional DNA sequencing.
Did you know?
Results from genetic testing usually take 1 to 2 weeks. Results from some methods, like fluorescence in situ hybridization (FISH) and immunohistochemistry, may be available in just a few days.
NSCLC accounts for around 80%–85% of all lung cancers, according to the American Cancer Society.
NSCLC can be divided into these subtypes:
The vast majority of NSCLC cases are either adenocarcinoma or squamous cell carcinoma, with adenocarcinoma being the most common NSCLC subtype.
Once you know which subtype of NSCLC you have, the next step is usually to determine the specific gene mutations that might be involved.
There are many treatments for NSCLC. Because NSCLCs can differ, treatment must be carefully considered.
Detailed testing can determine if your tumor has particular gene mutations or proteins. Targeted therapies are designed to treat the specific characteristics of the tumor.
Below are some targeted therapies for NSCLC.
KRAS
KRAS inhibitors include sotorasib (Lumakras) and adagrasib (Krazati).
EGFR
EGFR inhibitors block the signal from the EGFR gene that encourages growth. They may target one or multiple types of EGFR mutations.
Examples include these oral medications:
These EGFR inhibitors can eventually stop working. When that happens, your doctor may order an additional tumor biopsy to see whether your cancer has mutations that may respond to osimertinib (Tagrisso). It's also an EGFR inhibitor.
Necitumumab (Portrazza) is an EGFR inhibitor given via intravenous (IV) infusion. It must be combined with the chemotherapy drugs gemcitabine (Infugem) and cisplatin.
EGFR exon 20 insertion
There are two medications available to treat this mutation:
They're given to people who've already tried chemotherapy.
ALK
Therapies that target abnormal ALK proteins include:
These medications can be used in place of chemotherapy or after chemotherapy has stopped working.
If you have the EML4-ALK mutation, you would also receive one of these treatments.
MET and METex14
Cancers involving the METex14 mutation can be treated with the following targeted therapies:
There are currently no targeted therapies for other MET mutations.
Other targeted therapies
There are no established targeted therapies for lung cancers with the NRAS, PIK3CA, and TP53 mutations.
Other targeted therapies include:
The Food and Drug Administration (FDA) has only approved ceritinib (Zykadia) and lorlatinib (Lorbrena) to treat ALK-positive lung cancer.
However, a doctor may still prescribe if you have ROS1-positive lung cancer. This is known as off-label drug use.
OFF-LABEL DRUG USE
Off-label drug use means a drug that's approved by the Food and Drug Administration (FDA) for one purpose is used for a different purpose that hasn't yet been approved.
However, a doctor can still use the drug for that purpose. This is because the FDA regulates the testing and approval of drugs but not how doctors use drugs to treat their patients.
So your doctor can prescribe a drug however they think is best for your care.
If you have been diagnosed with lung cancer or are concerned about symptoms, it's important to speak with your doctor about all of your options.
Genetic testing can tell you and your doctor more about your treatment needs.
Targeted therapies for NSCLC are some of the most promising treatments so far, and their number continues to grow.
We can expect to see advances as researchers learn more about specific gene mutations that cause NSCLC to progress. More research is being done to increase treatment effectiveness and provide a better outlook for people with this type of lung cancer.
BRAF Mutation In Non-Small Cell Lung Cancer: Your FAQs Answered
The BRAF (V-Raf murine sarcoma viral oncogene homolog B) mutation refers to a change in the BRAF gene and protein. BRAF proteins and MEK proteins help control the growth and spread of healthy cells.
The BRAF mutation occurs in the gene. It causes the creation of defective BRAF proteins. When this happens, it can lead to uncontrolled cell growth and cancer.
Though several mutations can occur within the BRAF gene, the most common one in lung cancer is BRAF V600E. The Food and Drug Administration (FDA) has approved certain medications to treat it.
The BRAF mutation can act as a biomarker in lung cancer. This means that the presence of abnormal BRAF mutations in a biopsy or blood work can indicate the presence of lung cancer.
Finding the mutation can also help your healthcare team determine the best treatment for you after diagnosis.
The BRAF mutation occurs in about 3% to 5% of all NSCLCs, making it a rare type of lung cancer.
It's found almost exclusively in the adenocarcinoma subtype, which starts in the outer areas of the lungs.
NSCLC makes up about 80% to 85% of all types of lung cancers, and adenocarcinoma is the most common subtype of NSCLC.
When your healthcare professional determines you have the BRAF mutation, they will likely change their approach to your treatment.
The FDA has approved two first-line, targeted treatments for BRAF mutation-positive NSCLC. They are:
Dabrafenib and encorafenib target the defective BRAF gene, while trametinib and binimetinib target the mutated MEK gene. By correcting the genes, they stop the development of the defective proteins responsible for the cancer's growth, causing the cancer to shrink in size.
If the treatments fail or you have a non-V600E BRAF mutation, your healthcare team will likely recommend immunotherapy with or without chemotherapy.
Immunotherapy teaches your immune system to identify and destroy cancer cells in your body. Chemotherapy is a common form of cancer treatment that uses medications to kill cancer cells.
Depending on your situation, your healthcare team may also recommend or discuss the possibility of participating in a clinical trial. A clinical trial tests new medications and treatment methods to check how effective and safe they are.
Your healthcare professional will discuss your options and help guide you on the benefits and possible side effects of the different treatment types.
The BRAF mutation typically occurs spontaneously during a person's life. It may not be present at birth but can result from a change in the BRAF gene. This leads to defective BRAF proteins and triggers unregulated growth and division.
BRAF mutation-positive NSCLC often occurs in the following populations:
Your overall outlook and chances of survival when diagnosed with BRAF-positive NSCLC will depend on several factors.
Healthcare professionals will first determine the exact variation of the mutation. The FDA has only approved targeted treatments for BRAF V600E, as studies show they are more effective against this variation compared to non-V600E variations.
The ability to receive targeted treatments may improve your overall outlook and chances of survival.
If targeted therapy does not work, you may have success with immunotherapy. Depending on your health, age, and other considerations, a specialist may recommend chemotherapy alongside immunotherapy.
According to the results of a 2024 study, BRAF-positive NSCLC may positively affect outcomes when treated with immunotherapy. The study indicated that it may also be effective for advanced cases of NSCLC.
The exact survival rate for BRAF-positive NSCLC is not well documented. According to the American Cancer Center, the 5-year survival rate of NSCLC (all types) is:
Five-year survival rates show how many people are alive 5 years after their initial diagnosis. These rates do not reflect the chances of survival, but they can give you and your healthcare team a way to discuss your outlook.
Who Gets Non-Small-Cell Lung Cancer?
Lung cancer is the one of the most common types of cancer doctors diagnose each year in the U.S. The most common kind of lung cancer is non-small-cell lung cancer (NSCLC).
It makes up around 84% of all lung cancer diagnoses. It's much more common than small-cell lung cancer (SCLC).
About 1 in 5 of all cancer deaths in the U.S. Are lung cancer deaths.
The overall 5-year survival rate (the percentage of people still living after 5 years with the disease) is 27%. The overall 5-year survival rate for NSCLC is slightly higher, at 28%.
Doctors talk about 5-year survival rates to help give you an idea of how you may fare with your disease. But many different factors can affect your specific disease course.
If your NSCLC is localized NSCLC, meaning it hasn't spread outside your lung, your overall 5-year survival rate is 65%.
If it's regional, meaning it has spread to nearby lymph nodes, the 5-year survival rate is about 37%.
Metastatic NSCLC that has spread to distant parts of your body has a 5-year survival rate of 9%.
Your chances of getting any type of cancer increase with age. Lung cancer is no exception. Most people who have it are 65 or older. The average age at diagnosis is 70. It's rare to get lung cancer when you're younger than 45.
Your age can also affect how well you do with your lung cancer treatment. Elderly people often don't respond as well to chemotherapy treatments.
Men are more likely to develop lung cancer than women are. Experts think this could be because men are more likely to smoke than women.
Rates of lung cancer cases have gone down across the board, but they've decreased at different rates for men and women. Men began having a decrease in the number of new lung cancer cases in the mid-1980s. That decrease for women happened later, in the mid-2000s.
And the decrease in numbers of men getting lung cancer is sharper than the decrease in women.
Between 2009 and 2018, the rate of lung cancer diagnoses dropped 1.4% each year in women. For men, it dropped 2.8% each of those years.
Studies on race and ethnicity on NSCLC survival rates show that the relationship isn't simple.
The CDC reports that the risk of getting lung cancer is highest in white people with a slightly lower risk in American Indian and Alaska Native people. Black people are the third most likely, followed by Asian Pacific Island people. People of Hispanic descent are the least likely to get the disease.
Both are the most likely groups to get the disease. American Indian and Alaska Native people are the third most likely, followed by Asian and Pacific Island people. People of Hispanic descent are the least likely to get the disease, with half the rate of Black and white people.
Black men are about 12% more likely to get lung cancer than white men. For women, the difference flips: The rate is around 16% lower in Black women than in white women.
Overall lung cancer survival tends to be lower in lower-income neighborhoods than in higher-income communities.
Part of the reason for this is access to preventative care. Annual lung cancer screening can reduce the chances of dying from the disease by 20% if you're in a high-risk category.
But people with lower incomes are less likely to qualify for these lung cancer screenings. And among those who do qualify, screening rates continue to be lower for people who live at or below the poverty line.
Research shows that your socioeconomic status – your race, ethnicity, and financial stability – has an impact on a lung cancer diagnosis, even after taking into account your smoking habits and age.
You're at a higher risk of getting lung cancer if you have a lower socioeconomic status.
People without health insurance typically get a lung cancer diagnosis at a later stage of the disease than those who have insurance. A late diagnosis can mean you have a worse prognosis.
Being uninsured or having inadequate health insurance raises your risk of death after a lung cancer diagnosis.
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