The factor that contributed to cancer is :
- Alcohol
- diet
- environmental aspect
- family history/background
- sedantary lifestyle
- smoking
- sun exposure
- viruses and other infections
But from the observation and research ,the most causes of cancer is smoking, because of the chemical compound ingredient inside it can harmly damage the tissues or organ inside our bodies, as the result we suffered the lung cancer that can killed us.
EXAMPLE OF PICTURE : LUNG CANCER
references : http://www.intelihealth.com/IH/ihtIH/WSIHW000/8096/24516/294899.html?d=dmtContent