Lung cancer
What is lung cancer?
Lung cancer is the leading cause of cancer deaths in the United States and worldwide. Approximately 85% of lung cancer occurs in current or former tobacco smokers.
Lung cancer forms in the tissues of the lungs, usually in the cells lining air passages. The two most common types are small cell lung cancer and non-small cell lung cancer. Lung cancer that is detected early, before it spreads (metastasizes) to other parts of the body, can be more successfully treated.
What are the risk factors for lung cancer?
Lung cancer risk factors include:
- Tobacco smoke. Smoking is by far the leading risk factor for lung cancer. At least 80% of lung cancer deaths are thought to result from smoking. The risk for lung cancer among smokers is many times higher than among non-smokers. The longer you smoke and the more packs a day you smoke, the greater your risk.
- Radon is a naturally occurring radioactive gas that results from the breakdown of uranium in soil and rocks. It cannot be seen, tasted or smelled. Outdoors, there is so little radon that it is not likely to be dangerous. But indoors, radon can be more concentrated. When it is breathed in, it enters the lungs, exposing them to small amounts of radiation. This may increase a person’s risk of lung cancer.
- Workplace exposure to asbestos fibers is an important risk factor for lung cancer. Studies have found that people who work with asbestos (in some mines, mills, textile plants, places where insulation is used, shipyards, etc.) are several times more likely to die of lung cancer.
- Personal or family history of lung cancer. Brothers, sisters and children of those who have had lung cancer may have a slightly higher risk of lung cancer themselves, especially if the relative was diagnosed at a younger age. It is not clear how much of this risk might be due to inherited genes and how much might be from shared household exposures (such as tobacco smoke or radon).
What are the symptoms of lung cancer?
Most lung cancers do not cause any symptoms until they have spread too far to be cured, but symptoms do occur in some people with early lung cancer. If you go to your doctor when you first notice symptoms, your cancer might be diagnosed at an earlier stage, when treatment is more likely to be effective.
The most common symptoms of lung cancer are:
- A cough that does not go away or gets worse
- Chest pain that is often worse with deep breathing, coughing or laughing
- Hoarseness
- Weight loss and loss of appetite
- Coughing up blood or rust-colored sputum (spit or phlegm)
- Shortness of breath
- Feeling tired or weak
- Infections such as bronchitis and pneumonia that don’t go away or keep coming back
- New onset of wheezing
How is lung cancer diagnosed?
Lung cancer screening: Screening examinations are tests performed to find disease before symptoms begin. The goal of any screening is to detect disease at its earliest and most treatable stage. Current recommendations for lung cancer screening are based on risk factors for lung cancer.
- Potential screening benefits: Effective research proven screening exam; early diagnosis which can lead to improved outcomes; non-invasive testing; decreased radiation exposure.
- Potential screening risks: False positive test results; false negative test results; finding late-stage cancer; over-treatment including additional tests or procedures; radiation exposure.
Computed tomography (CT) scanning combines special X-ray equipment with sophisticated computers to produce pictures of the inside of the body. Low-dose CT (LDCT) scans produce images of sufficient quality to detect many lung diseases or abnormalities but use up to 70% less radiation than a regular CT scan. The scan is normally performed while lying on your back on a table. No IV or oral contrast medications are required for LDCT.
How is lung cancer treated?
Lung cancer is treated in several ways, depending on the type of lung cancer and how far it has spread. Treatments include:
- Surgery: Doctors remove cancer tissue.
- Chemotherapy: Using special medicines to shrink or kill the cancer. The drugs can be pills you take or medicines given in your veins, or sometimes both.
- Radiation therapy: Using high-energy rays (similar to X-rays) to kill the cancer.
- Targeted therapy: Using drugs to block the growth and spread of cancer cells. The drugs can be pills you take or medicines given in your veins.
People with non-small cell lung cancer can be treated with surgery, chemotherapy, radiation therapy, targeted therapy, or a combination of these treatments. People with small cell lung cancer are usually treated with radiation therapy and chemotherapy.