tumor
Lung cancer is a disease in which the cells found in the lungs grow out of control. The growing mass of cells can form a tumor that pushes into nearby tissues. The tumor will affect how these tissues work. Lung cancer is the most common cause of cancer-related death in men, and the second most common in women. It is responsible for 1.3 million deaths worldwide every year Figure below . The most common symptoms are shortness of breath, coughing including coughing up blood , and weight loss. The most common cause of lung cancer is exposure to tobacco smoke.