Lung cancer is less common in those who do not smoke, but it can still occur. Two of the main contributors to nonsmoking lung cancer are secondhand smoke and a naturally occurring radioactive gas called radon.
According to the
This article discusses how lung cancer affects those who do not smoke. We also look at the symptoms, diagnosis, treatment options, and outlook.
People typically associate lung cancer with smoking. However, a considerable number of those who do not smoke develop lung cancer.
According to the American Cancer Society (ACS), approximately 20% of people who die from lung cancer in the U.S. each year have never smoked or used tobacco in other forms.
There are two main types of lung cancer: non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC).
According to the
- Adenocarcinoma: This is a type of NSCLC that starts in lung cells that make mucus. It accounts for 50–60% of lung cancers in nonsmokers.
- Squamous cell carcinoma: This is also a type of NSLCL. It starts in cells that line the airways of the lungs. Approximately 10–20% of nonsmokers with lung cancer have squamous cell carcinoma.
- SCLC: This type of lung cancer rarely affects those who do not smoke. Among those with lung cancer who do not smoke, only about 6–8% have SCLC.
The primary cause of lung cancer among people who have never smoked is radon, according to the Environmental Protection Agency (EPA).
Radon is a radioactive gas that comes from the breakdown of uranium in rocks and soils. It can seep into homes and other buildings, such as schools, where it may become concentrated.
Radon has no color or odor. A person must test their home to see if radon is present.
Other potential causes and risk factors include:
- Secondhand smoke: Approximately
7,000adults die each year from lung cancer that results from breathing in secondhand smoke. Breathing in secondhand smoke exposes a person to cancer-causing chemicals, according to the CDC.
- Air pollution: The chance of developing lung cancer increases slightly in cities or areas with heavy traffic.
- Other cancer-causing agents: These include carcinogens, such as uranium, asbestos, and diesel exhaust.
- Genetics: Changes in the lung cells can lead to lung cancer.
Lung cancer can affect those who have never smoked differently from those who have previously smoked.
A 2020 study examined 129,000 lung cancer cases across the U.S. In those who have never smoked, the researchers found that lung cancer was more prevalent among females and those between the ages of 20 and 49.
Additionally, lung cancer cells in those who have never smoked or those who have not smoked heavily may have particular genetic changes.
- epidermal growth factor receptor (EGFR)
- anaplastic lymphoma kinase (ALK)
- Kirsten rat sarcoma viral oncogene homolog (KRAS)
The symptoms of lung cancer are the
The American Lung Association (ALA) notes that in the early stages of lung cancer, many people do not have symptoms.
However, symptoms can inlcude:
- frequent coughing that worsens over time
- frequent lung infections, such as pneumonia or bronchitis
- coughing up blood
- continuous chest pain
- shortness of breath
If the cancer has spread to other parts of the body, a person may notice other symptoms including:
- appetite loss
- weight loss
- blood clots
- bone pain
- bone fractures
Treatment of lung cancer depends on several factors, according to ACS.
- the stage of the cancer
- an individual’s overall health
- the person’s lung function
- the traits of the cancer, such as genetics
The treatment for lung cancer may include one or more therapies:
- Surgery: A surgeon may remove the lobe of the lung that requires treatment or a smaller piece of the lung. In the early stages of cancer, surgery alone may be enough.
- Chemotherapy: This is a combination of drugs that aim to destroy cancer cells.
- Radiation therapy: This treatment uses beams of intense energy to destroy cancer cells.
- Radiofrequency ablation: This is when a thin probe sends high-energy radio waves into a tumor to heat and destroy cancer cells.
- Immunotherapy: A person takes drugs that boost the body’s ability to recognize and kill cancer cells.
- Targeted drug therapy: Treatment is based on specific genetic changes that have occurred in an individual’s cancer cells. A
2020 articlenotes that newly developed targeted therapies have shown promise due to the genetic mutations.
The outlook for someone with lung cancer depends on several factors.
According to the National Cancer Institute (NCI), these include:
- the type of lung cancer
- the stage of the cancer
- the tumor size
- the extent of cancer spread
- the presence of symptoms
According to the ALA, 18.6% of people with lung cancer will survive for 5 years or longer after their diagnosis. If the lung cancer has not spread, the survival rate is 56%.
A person can take certain steps to reduce the chance of developing lung cancer:
- Radon tests: As radon is a significant risk factor for developing lung cancer, people should have their home tested for radon.
- Secondhand smoke: A person can avoid public areas where smoking is allowed and not permit smoking in the home or car.
- Chemicals in the workplace: Someone who works around cancer-causing substances can talk to their employer about how to limit their exposure.
In addition, the ACS recommends a healthy diet containing high amounts of fruits and vegetables.
Healthcare professionals screen a person for lung cancer using low-dose computed tomography, which creates detailed images of the lungs.
There are currently no guidelines that recommend lung cancer screening in those who do not smoke.
If a person notices any symptoms of lung cancer, they should contact a healthcare professional as soon as possible.
Diagnosis of lung cancer typically starts with a physical exam and medical history.
If a healthcare professional suspects that a person might have lung cancer, they may request imaging tests, which include:
- chest X-ray
- computed tomography (CT) scan
- magnetic resonance imaging (MRI)
- positron emission tomography (PET) scan
- bone scan
A healthcare professional may also examine the cells under a microscope to confirm whether they are cancer cells.
The cells may come from:
- sputum, or saliva
- fluid around the lungs, which a doctor removes with a needle
- biopsy of a mass
Doctors might further analyze cancer cells to see if they have genetic changes that would make them viable candidates for certain drug treatments, called targeted therapies.
Lung cancer can develop in those who do not smoke and those who have never smoked.
The most common type of lung cancer in those who do not smoke is adenocarcinoma.
Taking steps such as avoiding secondhand smoke and testing one’s home for radon may help reduce the chance of developing lung cancer.