Lung cancer is one of the commonest cancers and cause of cancer related deaths all over the world. Cancer can grow in your body for a long time — years — before you know it’s there. Lung cancer often doesn’t cause symptoms in early stages. While there are many factors that can increase your risk of lung cancer, smoking any kind of tobacco products, including cigarettes, cigars or pipes is the biggest single risk factor. The treatment will depend on the type of lung cancer you have, where it is, how far it’s spread and many other factors.