英文是:Other cause of lung cancer include exposure to secondhand smoke,to asbestos and other industrial carcinogens,and to high concentrations of radon--an odorless gas that's released into the soil and water.Smokers exposed to asbestos and radon are more likely to develop cancer than are nonsmokers.
Lung cancer that begins in the lungs(primary lung cancer) is uncommon in nonsmokers,but cancer of the breast,colon,prostate,testide,kidney,thyroid,bone or other organs may spread to the lungs.In that case,the cancer is still referred to by the name of the organ in which it originate,rather than being called lung cancer.There's no connection between smoking and the spread of cancer cells to the lungs from other parts of the body.