Tobacco smoking may increase lung cancer development risk.

This study assessed the role of tobacco smoking in the development of lung cancer in Japanese men and women by meta-analysis. 8 cohort and 14 case-control studies were included in this meta-analysis. Researchers discovered that the risk of developing lung cancer was much higher in smokers than in non-smokers. The findings of this meta-analysis suggest that tobacco smoking may be a major contributing factor to the development of lung cancer in both men and women.