How does Lung Cancer Start?

Well, cancer anywhere in our body including lungs is an abnormal growth of abnormal cells that start growing rapidly, stealing nourishment from the normal cell depriving them of energy and hence suppressing them. This abnormal growth, cancer, is trigerred by various stimulants like abnormal genes, certain products, infections etc. The major trigger for lung cancer is smoking. Asbestos is another factor that stimulates the development of abnormal cells in lungs.