What Happens

Lung cancer may cause breathing or heart problems such as:

• Pleural effusion, which is the buildup of fluid between the outer lining of the lungs and the chest wall. This is a common condition with lung cancer.
• Coughing up large amounts of bloody sputum.
• Collapse of a lung (pneumothorax).
• Blockage of the airway (bronchial obstruction).
• Recurrent infections, such as pneumonia.
• Pericardial effusion, which is the buildup of fluid in the space between the heart and the sac around the heart (pericardium). This condition is not common with lung cancer.

As lung cancer grows, it may spread (metastasize) to other parts of the body. Lung cancer is classified in stages that are determined by the size of the cancer and how far it has spread within the lung, to nearby tissues, or to other organs.

Your doctor determines the stage of your lung cancer by gathering information from a variety of tests, including bone scans, PET scans, CT scans, and X-rays. The stage of your cancer is one of the most important factors in choosing an effective treatment.

The long-term outcome (prognosis) for lung cancer depends on how much the cancer has grown and spread. Experts talk about prognosis in terms of "5-year survival rates." The 5-year survival rate means the percentage of people who are still alive 5 years or longer after their cancer was discovered. Because lung cancer is often diagnosed at an advanced stage, only 15% of people live 5 or more years after being diagnosed.⁵ It is important to remember that these are only averages. Everyone's case is different, and these numbers do not necessarily show what will happen to you.