Lung Cancer Overview
What Is It?
One of the most common cancers, lung cancer usually occurs when a cancer-causing agent, or carcinogen, triggers the growth of abnormal cells in the lung. These cells multiply out of control and eventually form a tumor. As the tumor grows, it destroys nearby areas of the lung. Eventually, tumor cells can spread (metastasize) to nearby lymph nodes and other parts of the body. These include the
In most cases, the carcinogens that trigger lung cancer are chemicals found in cigarette smoke. However, relatively more lung cancers are being diagnosed in people who have never smoked. But this still accounts for a minority of new cases.