There’s no doubt lung cancer has a genetic component.
you could inherit genetic mutations (alterations in your genes) that increase your risk for lung cancer.
However, you acquire most mutations during your lifetime.
Illustration by JR Bee, Verywell
Influencing Factors
Family history alone can’t predict if you will or will not get lung cancer.
Familial lung cancer is a term that suggests a cancer gene is passed from parents to children.
Interestingly, within this younger population, few are smokers.
These disparities indicate familial and genetic influences have a role.
However, more research is needed to determine the underlying risk factors.
Race
Race and ethnicity are also differentiating factors in the risk of lung cancer.
Gene Mutations
Lung cancers are linked toinherited and acquiredgenetic mutations, but most are acquired.
An acquired genetic modification happens when health issues or environmental toxins affect your genes.
When genes change, they alter the function and life cycle of healthy cells.
Genetic changes cause cells to replicate abnormally and grow out of control, which leads to cancer.
Having a genetic mutation doesn’t mean you’ll get lung cancer.
However, it reflects a risk that you may prevent with lifestyle changes like quitting smoking.
Scientists have identified the following genes associated with carcinogenesis (the development of cancer) in the lungs.
EGFR
Mutations of theEGFR genecan alter the production of a protein called epidermal growth factor receptor.
This protein helps cells respond appropriately to their environment.
Research suggests that 47% of Asians with NSCLC have an EGFR mutation.
EGFR mutations are also more common in women and non-smokers.
While these mutations are mainly linked to lung adenocarcinomas, some can affectsquamous cell carcinomasby making them more aggressive.
Some EGFR mutations are inherited; others are acquired.
When these genes are altered, they tend to become resistant to the drugs used to treat them.
KRAS
The KRAS gene is responsible for the production of a signaling protein called K-Ras.
K-Ras tells cells how to divide, mature, and function.
Dysregulation of this protein leads to uncontrolled cell growth and cancer.
A KRAS mutation is also more common in smokers than non-smokers.
Screening and Treatment
Scientists still have much to learn about the genetics of lung cancer.
As a result, there are currently no recommendations regarding preventive genetic screening.
(Genetic screening shouldn’t be confused with lung cancer screening to detect the disease before symptoms appear.)
However, genetic testing is routine after lung cancer is diagnosed.
Genetic Testing Improves Treatment
Genetic testing reveals the specific mutation behind each person’s lung cancer.
Oncologists often combine targeted therapy (personalized medicine) with conventional treatments like surgery and chemotherapy.
However, targeted medications work differently from other lung cancer therapies.
These drugs target and kill cancer cells while leaving healthy cells untouched.
They may inhibit the growth of new blood vessels or target genetic mutations.
While no one can predict how long youll live,lung cancer survival ratescan give you a general estimate.
When non-small cell lung cancer is treated before it spreads, 65% of people survive five years.
If the cancer spreads to another body area, the survival rate drops to 9%.
Survival rates are significantly lower if you have small-cell lung cancer because it grows rapidly.
Genetics Can Affect Life Expectancy
Genetics have a dual role in life expectancy after lung cancer develops.
Some inherited genetic alterations cause small cell lung cancer thats more aggressive and faster to spread.
The same cancer also has DNA pathways that cancer specialists can target with personalized treatment.
The same genetic differences that cause more severe cancer can also improve treatment response.
Cancers brought on by certain gene mutations are more likely to respond to standard chemotherapy.
They may also stay in remission longer compared to lung cancer patients who dont have genetic changes.
Summary
Lung cancer begins when genes are altered, forcing cells to divide and grow too rapidly.
As a result, a cancerous tumor develops.
Some genetic mutations are inherited, but most are acquired from exposure to toxins throughout your lifetime.
Genetic testing to identify the mutation responsible for each person’s lung cancer is essential for guiding treatment.
Drugs that target specific genetic changes can slow cancer growth and help treat lung cancer.
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