Incidence in the US for individuals age 40-79 years ranges from 4.8-13.7-100,000 person-years for men and 14.4-20.8 her 100,000 person-years for women (Wakelee HA).
The incidence of non-small cell lung cancer has more than doubled among nonsmoker to nearly 28%of such cancers (Lim ES).
No single major risk factor has been identified but potential risk factors include environmental exposure to smoke, radon, cooking fumes, asbestos, oncogenic viruses, hormone factors and genetic susceptibility.
Lung cancer can be caused by many risk factors other than smoking cigarettes, pipes, or cigars.
These risk factors 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 radonexternal icon to about 2,900 of these lung cancers.
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.
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.external icon
The U.S. Preventive Services Task Force does not recommend lung cancer screeningfor people who have never smoked.
About 50% to 60% of lung cancers found in people who never smoked are adenocarcinomas, About 10% to 20% are squamous cell carcinomas, and 6% to 8% are small cell lung cancers.
Increases the risk of lung cancer in never smokers by 20-30% based on analysis of more than 100 studies.
Environmental tobacco smoke may account for only a small number lung cancer cases in non smokers.
Exposure to rapesee oil fumes associated with an increased risk of lung cncer in Chinese women with a relative risk of 2.6 (Gao YT).
Exposure to cooking and indoor heating reported to be associated with an increaed risk of lung cancer in Chinese populations (Kleinerman RA).
Risk of developing lung cancer in never smokers associated with a family history of lung with a relative risk of 1.51 (Matakidou A).
Two single nucleotide polymorphisms on chromosome 15q25 associated with an increased risk of developing lung cancer in non smokers(Hung RJ, Amos CL).
Next generation sequencing reveal driver alterations in 95% of never smokers, with the majority having associations with an available targeted therapy.