Lung carcinoma is a malignant tumor in tissues of the lung. If untreated, the tumor growth can spread beyond the lung by process of metastasis to other parts of the body. Respiratory symptoms like wheezing, coughing up blood, coughing, shortness of breath, fever, weight loss are the main symptoms which have seen in the cases of lung cancer. Smoking, radon gas, asbestos, air pollution, genetic inheritances are the main causes of lung cancer. Mutation inn K-ras gene is responsible for lung adenocarcinoma. Lung cancer mainly diagnosed by chest radiography. It is classified as two broad areas i.e. non-small cell lung carcinoma and small cell lung carcinoma.