Basic Information

Lung cancers are cancers that begin in the lungs. Other types of cancers may spread to the lungs from other organs. However, these are not lung cancers because they did not start in the lungs. When cancer cells spread from one organ to another, they are called metastases.

Research has found several risk factors for lung cancer. A "risk factor" is anything that changes risk of getting a disease. Different risk factors change risk by different amounts.

The risk factors for lung cancer include:

    * smoking and being around others' smoke
    * things around us at home or work (such as radon gas)
    * personal traits (such as having a family history of lung cancer)

Drawing of the chest diagramming the lungs, alveoli, bronchus, and bronchiole. The right lung has 3 sections, or lobes, and the left lung has 2 lobes. Lung cancers are cancers that begin in the lungs. Other types of cancers may spread to the lungs from other organs. However, these are not lung cancers because they did not start in the lungs. When cancer cells spread from one organ to another, they are called metastases.

Fast Facts

According to the United States Cancer Statistics: 2004 Incidence and Mortality report, lung cancer is:

    * the second most common cancer among white, black, Asian/Pacific Islander, and American Indian/Alaska Native men, and the third most common cancer among Hispanic men, in the United States


    * the second most common cancer among white and American Indian/Alaska Native women, and the third most common cancer among black, Asian/Pacific Islander, and Hispanic women, in the United States

In 2004 (the most recent year for which statistics are currently available):

    * 108,355 men and 87,897 women were diagnosed with lung cancer
    * 89,575 men and 68,431 women died from lung cancer

For more information about lung cancer rates, visit Statistics.

*Incidence counts cover approximately 98% of the U.S. population; death counts cover 100% of the U.S. population. Use caution in comparing incidence and death counts.

Source: U.S. Cancer Statistics Working Group. United States Cancer Statistics: 2004 Incidence and Mortality. Atlanta (GA): Department of Health and Human Services, Centers for Disease Control and Prevention, and National Cancer Institute; 2007.

    
Symptoms

Different people have different symptoms for lung cancer. Some people don't have any symptoms at all. About 25% of people with lung cancer do not have symptoms from advanced cancer when their lung cancer is found.1 Lung cancer symptoms may include:

    * shortness of breath
    * coughing that doesn't go away
    * wheezing
    * coughing up blood
    * chest pain
    * fever
    * weight loss

Other changes that can sometimes occur with lung cancer may include repeated bouts of pneumonia, changes in the shape of the fingertips, and swollen or enlarged lymph nodes (glands) in the upper chest and lower neck.

These symptoms can happen with other illnesses, too. People with symptoms should talk to their doctor, especially if they smoke, but even if they don't. Doctors can help find the cause. 2, 3
References

   1. Humphrey LL, Teutsch S, Johnson MS. Lung Cancer Screening with Sputum Cytologic Examination, Chest Radiography, and Computed Tomography: An Update for the U.S. Preventive Services Task Force.* Annals of Internal Medicine 2004;140:740–753.
   2. Harrison's Principles of Internal Medicine, Chapter 88: Neoplasms of the lung. Clinical Manifestations. P.3. The McGraw-Hill Companies, Inc., 2008.
   3. Beckles MA, Spiro SG, Colice GL, Rudd RM. Initial evaluation of the patient with lung cancer: Symptoms, signs, laboratory tests and paraneoplastic syndromes.* Chest 2003;123:97S–104S.

Diagnosis and Treatment

A person’s lung cancer diagnosis depends on the type of lung cancer present. The two main types of lung cancer are small cell lung cancer and non-small cell lung cancer. Non-small cell lung cancer is more common than small cell lung cancer. These categories refer to what the cancer cells look like under a microscope.

The extent of disease is referred to as the stage. Information about how big a cancer is or how far it has spread is often used to determine the stage. Doctors use information about stage to plan treatment and to monitor progress.

For more information about stages of lung cancer, visit the National Cancer Institute (NCI) Physician Data Query (PDQ) sites on Stages of Non-Small Cell Lung Cancer and Stages of Small Cell Lung Cancer.

There are several ways to treat lung cancer. The treatment depends on the type of lung cancer and how far it has spread. Treatments include surgery, chemotherapy, and radiation. People with lung cancer often get more than one kind of treatment. (Visit the NCI PDQ for more information about treatments for Non-Small Cell Lung Cancer and Small Cell Lung Cancer. This site also has a directory of healthcare providers involved in cancer care. See also "Related Links" for more information about treatment and links to aids that can help with treatment choices.1)

Surgery
Doctors cut out and remove cancer tissue in an operation.

Chemotherapy
Chemotherapy involves the use of drugs to shrink or kill the cancer. The drugs could be pills or medicines given through an IV (intravenous) tube. Sometimes chemotherapy includes both IV drugs and pills.

Radiation
Radiation uses high-energy rays (similar to x-rays) to try to kill the cancer cells. The rays are aimed at the part of the body where the cancer is.

These treatments may be provided by different doctors on your medical team. Pulmonologists are doctors that are experts in diseases of the lungs. Surgeons are doctors that perform operations. Medical oncologists are doctors that are experts in cancer and treat cancers with medicines. Radiation oncologists are doctors that treat cancers with radiation.

Clinical Trials
People with lung cancer may want to take part in a clinical trial. Clinical trials study new potential treatment options. Visit the NCI, National Institutes of Health (NIH), and American Cancer Society (ACS) sites listed below for more information about finding clinical trials.

    * Learning About Clinical Trials
    * PDQ
    * Finding Clinical Trials
    * Clinical Trials
    * Clinical Trials*

Complementary and Alternative Medicine
For information about complementary and alternative medicine, visit the Physician Data Query site on Complementary and Alternative Medicine.

A recent review of cancer care in the United States found that some cancer patients are not benefiting from advances in cancer care as much as others. To learn more about these issues, visit the Institute of Medicine Reports on Ensuring Quality Cancer Care* and The Unequal Burden of Cancer.* 2, 3
References

   1. DeVita VT, Hellman S, Rosenberg SA. Cancer: Principles and Practice of Oncology, 6th Edition.
   2. Institute of Medicine (IOM), National Research Council, National Cancer Policy Board. Ensuring Quality Cancer Care. National Academy Press, Washington, D.C., 1999.
   3. Institute of Medicine (IOM), Committee on Cancer Research Among Minorities and the Medically Underserved. The Unequal Burden of Cancer.* National Academy Press, Washington, D.C., 1999.
      

Survivorship

People with lung cancer may experience symptoms caused by the cancer or by cancer treatments (side effects). Common symptoms caused by lung cancer include shortness of breath, cough, wheeze, coughing up blood, pain, fever, and weight loss. Side effects vary depending on the type of treatment. People who want information about symptoms and side effects and those that can occur with their treatment plan should talk to their doctors. Also those with symptoms or concerns should discuss them with their doctors. Doctors can help answer questions and make a plan to control symptoms.

For more information about symptoms and side effects, visit the links to the National Cancer Institute (NCI) and the American Cancer Society (ACS) listed below.

    * Coping with Cancer
    * Symptoms and Side Effects*

For more information about finding or providing support for people with lung cancer and their caregivers, visit the links listed below.

    * Cancer Survivorship Initiative (CDC)
    * Survivorship Resources (CDC)
    * Support and Information for People Living with Cancer (CDC)
    * Questions for Your Doctor (NCI)
    * Patient Education and Support Programs (Lung Cancer Alliance)*

A recent study suggested that people diagnosed with lung cancer sometimes feel stigmatized by others.1 That is, that because of the association of smoking with lung cancer, some people felt blamed for causing their illness. Even some people who never smoked had similar feelings. For some, these feelings interfered with relationships or made them not want to talk to others about their cancer.

To learn more about this issue, visit the link to the American Cancer Society: Many Lung Cancer Patients Feel Stigmatized.*
Reference

   1. Chapple A, Ziebland S, McPherson A. Stigma, shame and blame experienced by patients with lung cancer: A qualitative study. BMJ 2004;328:1470.
      
    
Risk Factors

Research has found several risk factors for lung cancer. A "risk factor" is anything that changes risk of getting a disease. Different risk factors change risk by different amounts.

The risk factors for lung cancer include

    * smoking and being around others' smoke
    * things around us at home or work (such as radon gas)
    * personal traits (such as having a family history of lung cancer)

Smoking and Secondhand Smoke
Cigarette smoking causes lung cancer. In fact, smoking tobacco is the major risk factor for lung cancer. In the United States, about 90% of lung cancer deaths in men and almost 80% of lung cancer deaths in women are due to smoking. People who smoke are 10 to 20 times more likely to get lung cancer or die from lung cancer than people who do not smoke. The longer a person smokes and the more cigarettes smoked each day the more risk goes up. 1, 2, 3, 4, 5, 6, 7, 8

People who quit smoking have a lower risk of lung cancer than if they had continued to smoke, but their risk is higher than people who never smoked.7 As more people quit smoking, lung cancer rates will continue to fall, the percentage of lung cancers that occur in smokers will decrease, and the percentage of lung cancers that occur in people who have quit will rise.

Smoking also causes cancer of the voicebox (larynx,) mouth and throat, esophagus, bladder, kidney, pancreas, cervix, and stomach. More information about cigarette smoking and lung cancer is available in CDC's Smoking and Tobacco Use Fact Sheets, the Surgeon General's Report 2004, and the NCI Cigarette Smoking and Cancer Questions and Answers.

Using cigars or pipes also increases risk for lung cancer, but not as much as smoking cigarettes. For more information, visit the NCI Questions and Answers About Cigar Smoking and Cancer. 2, 3, 4, 8, 9, 10, 11

Smoke from other people's cigarettes ("secondhand" smoke) causes lung cancer as well. Secondhand smoke contains more than 4,000 chemicals, more than 50 of which cause cancer in people or animals. Every year, about 3,000 nonsmokers die from lung cancer due to secondhand smoke. 5, 12, 13, 14, 15, 16

For more information, visit Secondhand Smoke.

Things That May Cause Cancer at Home and Work
Several things may cause cancer (carcinogens) in the workplace or even in the home. For example, radon gas causes lung cancer and is sometimes found in people's homes. Radon is an odorless, colorless gas that comes from rocks and dirt and can get trapped in houses and buildings. Examples of substances found at some workplaces that increase risk include asbestos, arsenic, and some forms of silica and chromium. For many of these substances, the risk of getting lung cancer is even higher for those who also smoke. 2, 3, 6, 17, 18, 19 Other substances may increase lung cancer risk as well.

For more information on carcinogens and cancer in the workplace, visit the links below.

    * Agency for Toxic Substances and Disease Registry ToxFAQs™
    * National Toxicology Program's 11th Report on Carcinogens
    * National Institute for Occupational Safety and Health

Family History
Risk of lung cancer may be higher if a person's parents, siblings (brother or sister), or children have had lung cancer. This increased risk could come from one or more things. They may share behaviors, like smoking. They may live in the same place where there are carcinogens such as radon. They may have inherited increased risk in their genes. 20, 21, 22, 23

For more information, visit the CDC's National Office of Public Health Genomics.

Diet
Scientists are studying many different foods to see how they may change the risk of getting lung cancer. However, any effect diet may have on lung cancer risk is small compared with the risk from smoking. Eating a lot of fat and cholesterol might increase risk of lung cancer. Drinking a lot of alcohol may raise risk as well. However, it's hard to tell how much of the risk in people who drink is actually due to tobacco smoke, since many people both smoke and drink.

Some foods may actually help prevent lung cancer. Diets high in fruits and vegetables likely decrease cancer risk. Diets high in vitamin C, vitamin E, or selenium might also help protect against lung cancer. The effect of eating foods with carotenoids, like beta-carotene, on lung cancer risk is currently uncertain. Carotenoids can be found in carrots, sweet potatoes, and some green vegetables. Eating these foods may lower chances of lung cancer. Taking beta-carotene supplements (pills) is not recommended, however, since it may actually increase risk in some smokers. 6, 8, 24, 25, 26

For more information, visit the National Cancer Institute's Diet and Cancer.


Reducing Risk

There may be several ways to reduce the risk of developing lung cancer.

Don't Smoke
Tobacco use is the major cause of lung cancer in the United States. About 90% of lung cancer deaths in men and almost 80% of lung cancer deaths in women in this country are due to smoking. The most important thing a person can do to prevent lung cancer is to not start smoking, or to quit if he or she currently smokes.

Quitting smoking will lower risk of lung cancer compared to not quitting. This is true no matter how old one is or how much he or she smokes. The longer a person goes without smoking, the more his or her risk will improve compared to those who continue to smoke. However, the risk in people who have quit is still higher than the risk in people who have never smoked.

For more information, visit Quit Smoking on CDC's Smoking and Tobacco Use site. 1, 2, 3, 4, 5, 6 Also, CDC helps support a national network of quitlines that makes free "quit smoking" support (www.smokefree.gov) available by telephone to smokers anywhere in the United States. The toll-free number is 1-800-QUITNOW (1-800-784-8669).

For smokers, avoiding other things that increase risk for lung cancer may help lower risk, but not as much as quitting smoking.

Avoid Secondhand Smoke
CDC's Office of Smoking and Health has information about secondhand smoke.

Make Your Home and Workplace Safer
The Environmental Protection Agency (EPA) recommends that all homes be tested for radon. Radon detectors can be purchased or arrangements can be made for qualified testers to come into the home. Visit the EPA radon Web site for more information about radon and radon testing. 7

Health and safety guidelines in the workplace can help workers avoid things that can cause cancer (carcinogens.)

Eat Lots of Fruits and Vegetables
Eating a diet high in fruits and vegetables may help protect against lung cancer. For more information, visit Fruits & Veggies - More Matters.
References

   1. International Agency for Research on Cancer (IARC). IARC Monographs on the Evaluation of Carcinogenic Risks to Humans and their Supplements: A complete list. Tobacco Smoking. Monograph Volume 38 (1986).
   2. International Agency for Research on Cancer (IARC). IARC Monographs on the Evaluation of Carcinogenic Risks to Humans and their Supplements: A complete list. Tobacco Smoking and Tobacco Smoke Volume 83 (2002). (PDF 48 Kb)*
   3. U.S. Department of Health, Education and Welfare. Smoking and Health: Report of the Advisory Committee to the Surgeon General of the Public Health Service (1964).
   4. U.S. Department of Health and Human Services. Women and Smoking: A Report of the Surgeon General (2001).
   5. Alberg AJ, Samet JM. Epidemiology of lung cancer.* Chest 2003;123:21S–49S.
   6. Institute of Medicine (IOM) National Cancer Policy Board. Fulfilling the Potential of Cancer Prevention and Early Detection. Curry SJ, Byers T, Hewitt M (eds). National Academies Press. Washington, D.C., 2003.
   7. U.S. Environmental Protection Agency. Indoor Air Quality: Radon.

    
Screening

Screening means testing for a disease when there are no symptoms or history of that disease. Doctors give a screening test to find a disease early on, when treatment may work better. Scientists have studied several types of screening tests for lung cancer. A review of these studies by experts shows that more information is needed (U.S. Preventive Services Task Force Recommendations). It is not known if these tests can help prevent deaths from lung cancer. 1

Examples of screening tests for lung cancer include:

    * chest x-rays
    * sputum cytology (looking for cancer cells in phlegm under a microscope)
    * CAT scans of the lungs (CAT scans are detailed images of the inside of the body, made by a computer that combines x-ray images taken from different angles.) 2

There is fair evidence that low-dose CAT scans, chest x-rays, and sputum cytology can find cancers earlier than they would be found without screening.

There is little evidence that these screening tests actually prevent people from dying from lung cancer. 1 Screening also has its downside. Screening tests may find spots (abnormalities) in the lungs that are not cancers. However, a screening test does not always show the difference between cancers and other abnormalities that are not cancers. More tests may be needed to find out if the spot is a cancer. These tests might include removing a small piece of lung tissue for more testing (biopsy). This means that some people might have a surgical procedure even though they don't have cancer. These procedures have risks associated with them. They also can cause anxiety and cost money.

Experts do not know if the benefits of screening outweigh the potential harms. For these reasons, experts do not currently recommend for or against lung cancer screening. Screening for lung cancer with chest x-rays was once promoted by some experts, but researchers found out that people who were screened did not have a lower death rate than people who were not screened.

Studies are underway that will help provide more information about the effectiveness of more modern screening tests. To learn more, visit the National Lung Screening Trial and the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. 1, 3
References

   1. U.S. Preventive Services Task Force. Lung Cancer Screening: Recommendation Statement.
   2. National Cancer Institute. Dictionary of Cancer Terms.
   3. Institute of Medicine (IOM) National Cancer Policy Board. Fulfilling the Potential of Cancer Prevention and Early Detection. Curry SJ, Byers T, Hewitt M (eds). National Academies Press. Washington, D.C., 2003.

Statistics

More people die from lung cancer than any other type of cancer. This is true for both men and women. In 2004 (the most recent year for which statistics are currently available), lung cancer accounted for more deaths than breast cancer, prostate cancer, and colon cancer combined.† In that year,

    * 108,355 men and 87,897 women were diagnosed with lung cancer*†
    * 89,575 men and 68,431 women died from lung cancer*†

Among men in the United States, lung cancer is the second most common cancer among white, black, Asian/Pacific Islander, and American Indian/Alaska Native men, and the third most common cancer among Hispanic men. Among women in the United States, lung cancer is the second most common cancer among white and American Indian/Alaska Native women, and the third most common cancer among black, Asian/Pacific Islander, and Hispanic women.†

*Note: Incidence counts cover 98% of the U.S. population and death counts cover 100% of the U.S. population. Use caution in comparing incidence and death counts.

†Source: U.S. Cancer Statistics Working Group. United States Cancer Statistics: 2004 Incidence and Mortality. Atlanta (GA): Department of Health and Human Services, Centers for Disease Control and Prevention, and National Cancer Institute; 2007.