Lung cancer is an uncontrolled growth of abnormal cells in the lungs. These abnormal cells often occur in groups, called "tumors." The cells can destroy normal, healthy tissue and can affect the way an organ functions. Like most forms of cancer, lung cancer can be treated and even cured if discovered in its earliest stages. But most lung cancers do not cause any symptoms until they have advanced too far to be cured.
Lung cancer is typically diagnosed through a chest x-ray after a patient has begun to show symptoms, or it is discovered when a chest x-ray is performed for another reason. Unfortunately, when the first symptoms (such as a cough) occur, the cancer usually has already grown to such an advanced stage that it can rarely be cured.
Smoking is, by far, the leading risk factor for lung cancer. Tobacco smoke causes more than 8 out of 10 cases of lung cancer. The longer a person has been smoking and the more packs per day smoked, the greater the risk. Smoking cigars and pipes actually carries a higher risk than cigarettes because they don't have filters. Exposure to "secondhand smoke" also increases your risk of developing lung cancer. Stopping smoking at any age reduces your risk.
Other risk factors include:
Although most lung cancers don't cause any symptoms until they have spread too far to be cured, symptoms sometimes occur in people with early lung cancer. If you visit your doctor when you first notice symptoms, your cancer might be diagnosed and treated while still in a curable stage. Or at the least, you could live longer with a better quality of life.
The American Cancer Society says the most common symptoms of lung cancer* are:
*These symptoms may be caused by lung cancer, or by other conditions. Be sure to check with your doctor to determine the cause.
Most experts agree that one single behavior-cigarette smoking-is responsible for more than 8 of every 10 cases of lung cancer. Preventing and reducing cigarette smoking are key to reducing illness and death from lung cancer.