Tobacco smoke contains more than 7,000 chemicals. About 70 of them are known to cause cancer. Smoking cigarettes is the number-one risk factor for lung cancer. But, smoking can affect your entire body, and is known to cause cancer in the:
Lungs
Trachea
Bronchus
Esophagus
Oral Cavity
Lip
Nasopharynx
Nasal Cavity
Larynx
Stomach
Bladder
Pancreas
Kidney
Liver
Uterine Cervix
Colon
Rectum
In addition, smoking is known to cause leukemia