Lung cancer is a type of cancer that occurs in the lungs. Your lungs are two spongy organs in your chest that take in oxygen when you inhale and free carbon dioxide when you exhale.
People who smoke have the highest risk of lung cancer, though lung cancer can also happen in people who have never smoked. The risk of lung cancer develops with the length of time and the number of cigarettes you’ve smoked. If you quit smoking, even after smoking for many years, you can significantly decrease your chances of developing lung cancer.
Signs and symptoms of lung cancer may include:
- A new cough that doesn’t go away
- Coughing up blood, even a small amount
- Shortness of breath
- Chest pain
- Losing weight without trying
- Bone pain
Risk factors for lung cancer include:
- Smoking. Your risk of lung cancer improves with the number of cigarettes you smoke each day and the number of years you have smoked. Stopping at any age can significantly reduce your risk of developing lung cancer.
- Exposure to secondhand smoke. Even if you don’t smoke, your risk of lung cancer develops if you’re exposed to secondhand smoke.
- Exposure to radon gas. Radon is created by the natural breakdown of uranium in soil, rock, and water that eventually becomes part of the air you breathe. Alarming levels of radon can accumulate in any building, including homes.
- Exposure to asbestos and other carcinogens. Workplace exposure to asbestos and other things are known to cause cancer — such as arsenic, chromium, and nickel — also can improve your risk of developing lung cancer, especially if you’re a smoker.
- Family history of lung cancer. People with a father, mother, sibling, or child with lung cancer have an enhanced risk of the disease.