Cancer is a disease in which cells in the body grow out of control. When cancer starts in the lungs, it is called lung cancer.

Lung cancer is one of the most common cancers in the United States. Skin cancer is the most common form of cancer diagnosed in the United States, followed by breast cancer (among women) and prostate cancer (among men). More people in the United States die from lung cancer than any other type of cancer. This is true for both men and women. After increasing for decades, lung cancer rates are decreasing nationally, as fewer people smoke cigarettes and as lung cancer treatments improve. People with lung cancer are living longer after their diagnosis because more cases are found early, when treatment works best.

Cigarette smoking is the number one cause of lung cancer. Lung cancer also can be caused by using other types of tobacco (such as pipes or cigars), breathing secondhand smoke, being exposed to substances such as asbestos or radon at home or work, having certain gene mutations (unusual changes made when your body’s cells are dividing), or having a family history of lung cancer. Lung cancer can happen in people who never smoked or smoked fewer than 100 cigarettes in their lifetime.

What is lung cancer?

Lung cancer is cancer that forms in tissues of the lung, usually in the cells that line the air passages. It is the leading cause of cancer death in both men and women.

There are two main types: small cell lung cancer and non-small cell lung cancer. These two types grow differently and are treated differently. Non-small cell lung cancer is the more common type.

Who is at risk for lung cancer?

Lung cancer can affect anyone, but there are certain factors that raise your risk of getting it:

• Smoking. This is the most important risk factor for lung cancer. Tobacco smoking causes about 9 out of 10 cases of lung cancer in men and about 8 out of 10 cases of lung cancer in women. The earlier in life you start smoking, the longer you smoke, and the more cigarettes you smoke per day, the greater your risk of lung cancer. The risk is also greater if you smoke a lot and drink alcohol every day or take beta carotene supplements. If you have quit smoking, your risk will be lower than if you had kept smoking. But you will still have a higher risk than people who never smoked.
• Secondhand smoke, which is the combination of smoke that comes from a cigarette and smoke breathed out by a smoker. When you inhale it, you are exposed to the same cancer-causing agents as smokers, although in smaller amounts.
• Family history of lung cancer
• Being exposed to asbestos, arsenic, chromium, beryllium, nickel, soot, or tar in the workplace
• Being exposed to radiation, such as from
  • Radiation therapy to the breast or chest
  • Radon in the home or workplace
  • Certain imaging tests such as CT scans
• HIV infection
• Air pollution

What are the symptoms of lung cancer?

Sometimes lung cancer does not cause any signs or symptoms. It may be found during a chest x-ray done for another condition.

If you do have symptoms, they may include

• Chest pain or discomfort
• A cough that doesn't go away or gets worse over time
• Trouble breathing
• Wheezing
• Blood in sputum (mucus coughed up from the lungs)
• Hoarseness
• Loss of appetite
• Weight loss for no known reason
• Fatigue
• Trouble swallowing
• Swelling in the face and/or veins in the neck

How is lung cancer diagnosed?

Your health care provider may use many tools to make a diagnosis:

• A medical history, which includes asking about your symptoms
• A family history
• A physical exam
• Imaging tests, such as a chest x-ray or chest CT scan
• Lab tests, including tests of your blood and sputum
• A biopsy of the lung

If you do have lung cancer, your provider will do other tests to find out how far it has spread through the lungs, lymph nodes, and the rest of the body. This is called staging. Knowing the type and stage of lung cancer you have helps your provider decide what kind of treatment you need.

What are the treatments for lung cancer?

For most patients with lung cancer, current treatments do not cure the cancer.

Your treatment will depend on which type of lung cancer you have, how far it has spread, your overall health, and other factors. You may get more than one type of treatment.

The treatments for small cell lung cancer include

• Surgery
• Chemotherapy
• Radiation therapy
• Immunotherapy
• Laser therapy, which uses a laser beam to kill cancer cells
• Endoscopic stent placement. An endoscope is a thin, tube-like instrument used to look at tissues inside the body. It may be used to put in a device called a stent. The stent helps to open an airway that has been blocked by abnormal tissue.

The treatments for non-small cell lung cancer include

• Surgery
• Radiation therapy
• Chemotherapy
• Targeted therapy, which uses drugs or other substances that attack specific cancer cells with less harm to normal cells
• Immunotherapy
• Laser therapy
• Photodynamic therapy (PDT), which uses a medicine and a certain type of laser light to kill cancer cells
• Cryosurgery, which uses an instrument to freeze and destroy abnormal tissue
• Electrocautery, a treatment that uses a probe or needle heated by an electric current to destroy abnormal tissue

Can lung cancer be prevented?

Avoiding the risk factors may help to prevent lung cancer:

• Quitting smoking. If you don't smoke, don't start.
• Lower your exposure to hazardous substances at work
• Lower your exposure to radon. Radon tests can show whether your home has high levels of radon. You can buy a test kit yourself or hire a professional to do the test.

Lung cancer can be caused by risk factors other than smoking cigarettes, pipes, or cigars. Examples include exposure to other people’s smoke (called secondhand smoke), radon, air pollution, a family history of lung cancer, and asbestos.

In the United States, about 10% to 20% of lung cancers, or 20,000 to 40,000 lung cancers each year, happen in people who never smoked or smoked fewer than 100 cigarettes in their lifetime. Researchers estimate that secondhand smoke contributes to about 7,300 and radon to about 2,900 of these lung cancers.

What Are the Symptoms of Lung Cancer Among People Who Never Smoked?

Symptoms of lung cancer are the same, whether or not you have smoked. Some people have general symptoms of not feeling well or feeling tired all the time. Some people cough frequently, cough up blood, or have chest pain, wheezing, or shortness of breath.

These symptoms can happen with other illnesses. If you have any of these symptoms, talk to your doctor, who can help find the cause.

How Can I Help Lower My Risk of Getting Lung Cancer?

You can help lower your risk of lung cancer by staying away from secondhand smoke, diesel exhaust, and other air pollution, as well as asbestos, arsenic, and some forms of silica and chromium. You should get your home tested for radon and take steps to lower the radon level if it is high.

Some risk factors, such as a personal or family history of lung cancer, can’t be changed. If lung cancer runs in your family, talk to your doctor about actions you can take stay healthy. People with lung cancer who have never smoked may have a DNA mutation, such as a mutation in the epidermal growth factor receptor (EGFR) gene or other genes. Cancers caused by these mutations may be treated with targeted therapy.

Is Lung Cancer Screening Recommended for People Who Never Smoked?

The U.S. Preventive Services Task Force does not recommend lung cancer screening for people who have never smoked. That’s because the possible harms of screening outweigh the possible benefit (finding lung cancer early) in this group.

What Types of Lung Cancer Are Diagnosed in People Who Never Smoked?

About 50% to 60% of lung cancers found in people who never smoked are adenocarcinomas (cancer that begins in the cells that line the lung’s tiny air sacs and make substances such as mucus). About 10% to 20% are squamous cell carcinomas (cancer that forms in the thin, flat cells lining the inside of the lungs). Adenocarcinomas and squamous cell carcinomas are two types of non-small cell lung cancer. A few (6% to 8%) are small cell lung cancers, and the rest are other types of lung cancer.

Non-Small Cell Lung Cancer (NSCLC)

Most lung cancers are classified as non-small cell lung cancer (NSCLC). About half of these are squamous cell carcinomas (SCC). SCC, sometimes called epidermoid carcinoma, is more prevalent in men and arises in the lining of the large air passageways, or bronchi. Another common type of NSCLC is adenocarcinoma, which occurs at the outer edges of the lung. A small percentage of NSCLC are large-cell carcinomas, which usually develop in the smaller bronchi. Non-small cell lung cancer that begins at the top of the lung sometimes spreads to the nerves and blood vessels leading to the arm.

All three subtypes of NSCLC develop differently. Treatment are often based on the location of the particular cancer and its rate of spread.

• Squamous cell or epidermoid carcinomas usually occur in the bronchi in the center of the lungs, but about a third of them arise on the periphery. This type of NSCLC is more likely to cause ulcers in the bronchi and bleeding than the other forms. Typically, the cancer cells double every 180 days. Although it often invades nearby tissue, squamous cell carcinoma is less likely to metastasize as soon as other types.
• Most adenocarcinomas begin in the middle of the lungs, but about 25 percent develop along the lung periphery. These tumors are small, and the cells double about every 180 days also. They are likely to metastasize early. The form known as bronchoalveolar adenocarcinoma develops in the alveoli and may spread through the airways to other parts of the lung.
• Large cell carcinomas are bulky tumors that usually develop on the organ's periphery; however, they can arise anywhere within the lung. The cells double about every 100 days and can invade the mediastinum during the course of the disease.

Small Cell Lung Cancer (SCLC)

About one in four malignancies involving the lungs are diagnosed as small cell lung cancer (SCLC). There are several types of SCLC or oat cell cancer, including a mix of small cell and other cell types. These cancers grow rapidly—doubling in cell number about every 30 days—and spread quickly to lymph nodes and other organs than the non-small cell type.

Research has found several risk factors that may increase your chances of getting lung cancer.

Smoking

Cigarette smoking is the number one risk factor for lung cancer. In the United States, cigarette smoking is linked to about 80% to 90% of lung cancer deaths. Using other tobacco products such as cigars or pipes also increases the risk for lung cancer. Tobacco smoke is a toxic mix of more than 7,000 chemicals. Many are poisons. At least 70 are known to cause cancer in people or animals.

People who smoke cigarettes are 15 to 30 times more likely to get lung cancer or die from lung cancer than people who do not smoke. Even smoking a few cigarettes a day or smoking occasionally increases the risk of lung cancer. The more years a person smokes and the more cigarettes smoked each day, the more risk goes up.

People who quit smoking have a lower risk of lung cancer than if they had continued to smoke, but their risk is higher than the risk for people who never smoked. Quitting smoking at any age can lower the risk of lung cancer.

Cigarette smoking can cause cancer almost anywhere in the body. Cigarette smoking causes cancer of the mouth and throat, esophagus, stomach, colon, rectum, liver, pancreas, voicebox (larynx), lung, trachea, bronchus, kidney and renal pelvis, urinary bladder, and cervix, and causes acute myeloid leukemia.

Secondhand Smoke

Smoke from other people’s cigarettes, pipes, or cigars (secondhand smoke) also causes lung cancer. In the United States, one out of four people who don’t smoke, including 14 million children, were exposed to secondhand smoke during 2013 to 2014.

Radon

After smoking, radon is the second leading cause of lung cancer in the United States. Radon is a naturally occurring gas that forms in rocks, soil, and water. It cannot be seen, tasted, or smelled. When radon gets into homes or buildings through cracks or holes, it can get trapped and build up in the air inside. People who live or work in these homes and buildings breathe in high radon levels. Over long periods of time, radon can cause lung cancer.

The U.S. Environmental Protection Agency (EPA) estimates that radon causes about 21,000 lung cancer deaths each year. The risk of lung cancer from radon exposure is higher for people who smoke than for people who don’t smoke. However, the EPA estimates that more than 10% of radon-related lung cancer deaths occur among people who have never smoked cigarettes. Nearly one out of every 15 homes in the United States has high radon levels.

Other Substances

Examples of substances found at some workplaces that increase risk include asbestos, arsenic, diesel exhaust, and some forms of silica and chromium. For many of these substances, the risk of getting lung cancer is even higher for those who smoke. Living in areas with higher levels of air pollution may increase the risk of getting lung cancer.

Personal or Family History of Lung Cancer

If you are a lung cancer survivor, there is a risk that you may develop another lung cancer, especially if you smoke. Your risk of lung cancer may be higher if your parents, brothers or sisters, or children have had lung cancer. This could be true because they also smoke, they live or work in the same place where they are exposed to radon and other substances that can cause lung cancer, or because of an inherited genetic mutation.

Radiation Therapy to the Chest

Cancer survivors who had radiation therapy to the chest are at higher risk of lung cancer.

Diet

Scientists are studying many different foods and dietary supplements to see whether they change the risk of getting lung cancer. There is much we still need to know. We do know that people who smoke and take beta-carotene supplements have increased risk of lung cancer.

Also, arsenic and radon in drinking water (primarily from private wells) can increase the risk of lung cancer.

Different people have different symptoms for lung cancer. Some people have symptoms related to the lungs. Some people whose lung cancer has spread to other parts of the body (metastasized) have symptoms specific to that part of the body. Some people just have general symptoms of not feeling well. Most people with lung cancer don’t have symptoms until the cancer is advanced. Lung cancer symptoms may include—

• Coughing that gets worse or doesn’t go away.
• Chest pain.
• Shortness of breath.
• Wheezing.
• Coughing up blood.
• Feeling very tired all the time.
• Weight loss with no known cause.

Other changes that can sometimes occur with lung cancer may include repeated bouts of pneumonia and swollen or enlarged lymph nodes (glands) inside the chest in the area between the lungs.

These signs and symptoms can happen with other illnesses, too. If you have some of these signs and symptoms, talk to your doctor, who can help find the cause.

Screening means testing for a disease when there are no symptoms or history of that disease. Doctors recommend a screening test to find a disease early, when treatment may work better.

The only recommended screening test for lung cancer is low-dose computed tomography (also called a low-dose CT scan, or LDCT). During an LDCT scan, you lie on a table and an X-ray machine uses a low dose (amount) of radiation to make detailed images of your lungs. The scan only takes a few minutes and is not painful.

Who Should Be Screened?

The U.S. Preventive Services Task Force (USPSTF) recommends yearly lung cancer screening with LDCT for people who—

• Have a 20 pack-year or more smoking history, and
• Smoke now or have quit within the past 15 years, and
• Are between 50 and 80 years old.

A pack-year is smoking an average of one pack of cigarettes per day for one year. For example, a person could have a 20 pack-year history by smoking one pack a day for 20 years or two packs a day for 10 years.

Risks of Screening

Lung cancer screening has at least three risks—

• A lung cancer screening test can suggest that a person has lung cancer when no cancer is present. This is called a false-positive result. False-positive results can lead to follow-up tests and surgeries that are not needed and may have risks.
• A lung cancer screening test can find cases of cancer that may never have caused a problem for the patient. This is called overdiagnosis. Overdiagnosis can lead to treatment that is not needed.
• Radiation from repeated LDCT tests can cause cancer in otherwise healthy people.

That is why lung cancer screening is recommended only for adults who are at high risk for developing the disease because of their smoking history and age, and who do not have a health problem that substantially limits their life expectancy or their ability or willingness to have lung surgery, if needed.

If you are thinking about getting screened, talk to your doctor. If lung cancer screening is right for you, your doctor can refer you to a high-quality screening facility.

Some people with a smoking history may blame themselves or feel that others blame them for being at risk for getting cancer. Lung cancer can be caused by many different things. If you do get lung cancer, lung cancer screening can help find it early, when treatment may work better.

When you get lung cancer screening, your doctor may ask you if you smoke, ask if you’re ready to quit smoking, and tell you about proven steps that can help you quit. No matter how long you have used tobacco, quitting can reduce your risk for lung cancer and other chronic diseases. Many people who use tobacco become addicted to nicotine, a drug found naturally in tobacco. This can make it hard to quit using tobacco. Most people who use tobacco try to quit several times before they succeed. For more information about quitting tobacco use, visit smokefree.gov.

When Should Screening Stop?

The Task Force recommends that yearly lung cancer screening stop when the person being screened—

• Turns 81 years old, or
• Has not smoked in 15 or more years, or
• Develops a health problem that makes him or her unwilling or unable to have surgery if lung cancer is found.

Insurance and Medicare Coverage

Most insurance plans and Medicare help pay for recommended lung cancer screening tests. If the screening test finds something abnormal, you may need more tests. These follow-up tests may have a cost such as a co-pay or deductible. Check with your insurance plan to find out what benefits are covered for lung cancer screening. For more information about Medicare coverage, visit www.medicare.gov or call 1-800-MEDICARE (1-800-633-4227). TTY users should call 1 (877) 486-2048.

Types of Lung Cancer

The two main types of lung cancer are small cell lung cancer and non-small cell lung cancer. These categories refer to what the cancer cells look like under a microscope. Non-small cell lung cancer is more common than small cell lung cancer.

If you have lung cancer (especially non-small cell lung cancer), your doctor may run tests to find out if you have a change in your genes (genetic mutation). The results of these tests help your doctor know which treatments will work best for you.

Staging

If lung cancer is diagnosed, other tests are done to find out how far it has spread through the lungs, lymph nodes, and the rest of the body. This process is called staging. The type and stage of lung cancer tells doctors what kind of treatment you need.

Screening can help find lung cancer at an early stage, when treatment may work better.

Types of Treatment

Lung cancer is treated in several ways, depending on the type of lung cancer and how far it has spread. 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.

• Surgery. An operation where doctors cut out 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. You will get tests to see if targeted therapy is right for your cancer type before this treatment is used.

Doctors from different specialties often work together to treat lung cancer. Pulmonologists are doctors who are experts in diseases of the lungs. Surgeons are doctors who perform operations. Thoracic surgeons specialize in chest, heart, and lung surgery. Medical oncologists are doctors who treat cancer with medicines. Radiation oncologists are doctors who treat cancers with radiation.

Clinical Trials

Clinical trials use new treatment options to see if they are safe and effective. For more information, visit the National Cancer Institute’s Clinical Trials page. If you have cancer, you may want to take part.

Complementary and Alternative Medicine

Complementary and alternative medicine are medicines and health practices that are not standard treatments doctors usually use to treat cancer.

• Complementary medicine is used in addition to standard treatments. Examples include acupuncture and meditation.
• Alternative medicine is used instead of standard treatments. Examples include special diets, megadose vitamins, herbal preparations, special teas, and magnet therapy.

Many kinds of complementary and alternative medicine have not been tested scientifically and may not be safe. Some complementary and alternative medicines may make your cancer medicine not work as well. Talk to your doctor about the risks and benefits before you start any kind of complementary or alternative medicine.

Which Treatment Is Right for Me?

Choosing the treatment that is right for you may be hard. Talk to your cancer doctor about the treatment options available for your type and stage of cancer. Your doctor can explain the risks and benefits of each treatment and their side effects. Side effects are how your body reacts to drugs or other treatments.

Sometimes people get an opinion from more than one cancer doctor. This is called a “second opinion.” Getting a second opinion may help you choose the treatment that is right for you.

When you have been diagnosed with cancer, you are considered a cancer survivor from that moment throughout the rest of your life.

Finding lung cancer earlier and making new treatments available are helping more lung cancer survivors live longer. We offer some tips to help you live with lung cancer as long and well as possible.

It’s important to get the treatment you need at the best time. You deserve timely and appropriate care for your lung cancer and its symptoms (including pain), as well as any side effects of treatment. Molecular testing (also called tumor or biomarker testing) may help you make decisions about treatment. You may also consider genetic testing to identify inherited characteristics.

Talk with your health care provider about how a survivorship care plan can help you coordinate your follow-up care to support your physical and emotional health.

Take steps to stay healthy. This can lower your risk of getting cancer again or having the cancer come back.

Some cancer survivors may blame themselves or feel that others blame them for having cancer. Lung cancer survivors may have feelings of blame or stigma. You may find it helpful to talk about your experiences and feelings with a social worker or other mental health professional. You may also find it helpful to share your story with other cancer survivors or listen to their stories.

You can help lower your risk of lung cancer in the following ways—

• Don’t smoke. Cigarette smoking causes about 80% to 90% of lung cancer deaths in the United States. The most important thing you can do to prevent lung cancer is to not start smoking, or to quit if you smoke.
• Avoid secondhand smoke. Smoke from other people’s cigarettes, cigars, or pipes is called secondhand smoke. Make your home and car smoke-free.
• Get your home tested for radon. The U.S. Environmental Protection Agency recommends that all homes be tested for radon.
• Be careful at work. Follow health and safety guidelines to avoid carcinogens (things that can cause cancer).