Many Lung Cancers Are Now in Nonsmokers. Scientists Want to Know Why.

Lung cancer in never-smokers accounts for 10-25% of global cases, reaching over 50% in some Asian and Asian American women. A study of 871 nonsmokers with lung cancer linked high air pollution to increased DNA mutations. Pollution directly harms DNA and accelerates cell division, contributing to cancer development. The cancer biology differs between smokers and nonsmokers, necessitating distinct prevention and detection approaches. Nonsmokers with lung cancer often exhibit specific "driver" mutations, unlike smokers' accumulation of numerous mutations. Current US lung cancer screening guidelines primarily target smokers. Taiwan's trial screening of nonsmokers with family history detected cancer in 2.6% of participants. This highlights the need for expanded screening criteria to include nonsmokers, especially in high-pollution areas. The findings underscore the significant impact of environmental factors in lung cancer development. Further research is crucial to refine prevention and early detection strategies for nonsmokers.