What to know
In the United States, about 10% to 20% of lung cancers, or 20,000 to 40,000 lung cancers each year, happen in people who never smoked or smoked fewer than 100 cigarettes in their lifetime.
Overview
Lung cancer can be caused by risk factors other than smoking cigarettes, pipes, or cigars. Examples include exposure to other people's smoke (called secondhand smoke), radon, air pollution, a family history of lung cancer, and asbestos.
In the United States, about 10% to 20% of lung cancers, or 20,000 to 40,000 lung cancers each year, happen in people who never smoked or smoked fewer than 100 cigarettes in their lifetime. Researchers estimate that secondhand smoke contributes to about 7,300 and radon to about 2,900 of these lung cancers.
Jackie’s Story
"You may not have symptoms," says Jackie, a lung cancer survivor who never smoked. "So test your house for radon." She shares her story in this video.
What are the symptoms of lung cancer among people who never smoked?
Symptoms of lung cancer are the same, whether or not you have smoked. Some people have general symptoms of not feeling well or feeling tired all the time. Some people cough frequently, cough up blood, or have chest pain, wheezing, or shortness of breath.
These symptoms can happen with other illnesses. If you have any of these symptoms, talk to your doctor, who can help find the cause.
How can I help lower my risk of getting lung cancer?
You can help lower your risk of lung cancer by staying away from secondhand smoke, diesel exhaust, and other air pollution, as well as asbestos, arsenic, and some forms of silica and chromium. You should get your home tested for radon and take steps to lower the radon level if it is high.
Some risk factors, such as a personal or family history of lung cancer, can't be changed. If lung cancer runs in your family, talk to your doctor about actions you can take stay healthy. People with lung cancer who have never smoked may have a DNA mutation, such as a mutation in the epidermal growth factor receptor (EGFR) gene or other genes. Cancers caused by these mutations may be treated with targeted therapy.
Is lung cancer screening recommended for people who never smoked?
The US Preventive Services Task Force does not recommend lung cancer screening for people who have never smoked. That's because the possible harms of screening outweigh the possible benefit (finding lung cancer early) in this group.
What types of lung cancer are diagnosed in people who never smoked?
About 50% to 60% of lung cancers found in people who never smoked are adenocarcinomas (cancer that begins in the cells that line the lung’s tiny air sacs and make substances such as mucus). About 10% to 20% are squamous cell carcinomas (cancer that forms in the thin, flat cells lining the inside of the lungs). Adenocarcinomas and squamous cell carcinomas are two types of non-small cell lung cancer. A few (6% to 8%) are small cell lung cancers, and the rest are other types of lung cancer.
Resources
- Radon and Your Health (CDC)
- Lung Cancer in Nonsmokers (Yale Medicine)
- Lung Cancer Risks for People Who Don't Smoke (American Cancer Society)