Lung cancer is the disease characterized by uncontrolled cells in tissues of the lung. If left unprocessed, this developmentcanextendafar from the lung in a procedure called metastasisinto adjacent tissues and, eventually into other parts of the body. Most cancers that start in lung, acknowledged as primary lung cancers, are carcinomas that derive from epithelial cells. The main types of lung cancer are minorcell lung carcinoma (SCLC), also called oat cell cancer, and non-small cell lung carcinoma (NSCLC). The most common cause of lung cancer is long-term exposure to tobacco smoke. Nonsmokers account for 15% of lung cancer cases, and these cases are often attributed to a combination of genetic factors, radon gas, asbestos, and air pollution including secondhand smoke.

The common symptoms of lung cancer are coughing, weight loss and shortness of breath. Lung cancer may be seen on chest radiograph and totaled tomography (CT scan). The diagnosis is confirmed with a biopsy. Lung cancer is the cancer that origin in lung. The lungs are located in chest. When you inhale, air drives through your nose, down your windpipe (trachea), and into the lungs, where it spreads through tubes called bronchi. Most lung cancer arises in the cells that line these tubes. Non-small lung cancer is the most common type of lung cancer and small lung cancer makes up about 20% of non-small lung cancer. If the cancer is buildup of both types it is called as mixed small cell/large cell cancer. And if the cancer originates in some other part of the body and spread in lungs it is called metastatic cancer to the lung.

Each year large number of people dies due to lung cancer than that of colon, breast, and prostate cancers combined. Cigarette smoking is one of the leading causes of lung cancer. It is more common among adults and rare in people below the age 45. The more cigarettes you smoke per day and the earlier you started smoking, the greater your risk for lung cancer. There is no evidence that smoking low-tar cigarettes lowers the risk. However, lung cancer can also occur in people who never smoke due to second hand smoke. Second hand smoke increases the risk of lung cancer.

Some other factors that increases the risk of lung cancer are Asbestos, Exposure to cancer-causing chemicals such as uranium, beryllium, vinyl chloride, nickel chromates, coal products, mustard gas, chloromethyl ethers, gasoline, and diesel exhaust, Family history of lung cancer, High levels of air pollution, High levels of arsenic in drinking water, Radiation therapy to the lungs, Radon gas etc.
Lung cancer at an early does not show any symptoms. However, symptoms completely depend on the type of cancer you have for example; coughing up blood, cough that does not go away, chest pain, fatigue, losing weight without trying, loss of appetite, shortness of breath and wheezing etc. lung cancer or any other type of cancer is found when an x-ray and CT scan is done. It is important to seek lung cancer specialist so as to live long lasting happy life.