The other deadliest form of cancer is the lung cancer. The common cause for this type of disease is the unhealthy habits of smoking the tobacco but the doctors also claim that this is not only the reason for the cause of the lung cancer. But it is estimated that almost eighty percentage of people who suffer from lung cancer are due to smoking but still even they quit the habit the chances of vulnerability is large and it depends on how much you have smoked previously. The functions of the lungs are known as it is useful for the function of breathing; the cancer gets developed in the line of the tubes called as bronchi. The Non-small cell lung cancer is the most common type of lung cancer and the other one is small cell lung cancer which is he cause for twenty percentage of lung cancer. This is one of the most deadly cancers as the treatments are much complicated as metastasis may happen.